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The testis-determining factor in the mouse is encoded by the Sry gene on the Y chromosome. Transcripts of this gene have been shown previously to be present in the genital ridge at the beginning of gonadal differentiation (11.5 days post coitum) and in adult testis. In this study, RNA transcripts of the Sry gene are also detected in male blastocyst-stage embryos (3.5 days post coitum) at approximately 40-100 copies per cell, long before overt sex differentiation. These results indicate that preimplantation mouse embryos have sexually dimorphic gene expression at least with respect to Sry transcripts. In addition, at least some of the Sry RNA transcripts in blastocysts are circular, as has been reported for Sry transcripts from adult testis. The appearance of Sry transcripts in blastocysts at this level raises the possibility that sex determination begins earlier during embryonic development than previously thought.

In a search for genes expressed in preimplantation mouse embryos that are important for the earliest steps in differentiation, we identified an abundant mRNA that codes for a sulfated glycoprotein, SGP-1. The amount of this RNA rises approximately 100-fold during preimplantation development to a level approximately equal to that of beta-actin mRNA in blastocysts, although the level of these transcripts per cell remains fairly constant during these stages at approximately 2,000-4,000 copies. An antisense RNA that is complementary to approximately the last one-third of the message and contains an open reading frame of 455 nt was found in blastocysts at a 2-3-fold higher level than the mRNA. In situ hybridization with sense and antisense riboprobes showed that both strands are distributed throughout the embryo. The abundance of the SGP-1 mRNA indicates that the encoded protein may play an important role in the development of embryos, and the excess of antisense RNA raises the possibility of an unusual mechanism of regulating its expression.

Phosphorothioate-modified oligonucleotides were injected into pregnant female mice to assess the effect on developing embryos. Injections were carried out during two different time periods, one when embryos were in preimplantation stages of development (about 3.5 days of development) and the other after implantation, when both a fetus and placenta are present (from days 9.5 to 11.5 of development). Three different phosphorothioate-modified oligonucleotides were injected. One, which had a sequence not present in the mouse genome, was used to ask whether nonspecific toxic or teratogenic effects on embryos result from treatment of the mother. A second was complementary to the mRNA of the testis-determining factor gene Sry and was used to ask whether a specific developmental pathway (i.e., sex determination) could be disrupted in embryos in vivo. The third was the complement of the anti-Sry sequence. None of these oligonucleotides reduced the frequency of successful pregnancy after mating or the average litter size from that observed in controls animals. Furthermore, examination of 291 pups or fetuses from all oligonucleotide-injected pregnant females revealed no developmental defects regardless of which sequence was used. It is concluded that injection of phosphorothioate-modified oligonucleotides into pregnant females according to the protocols described here is not toxic or teratogenic to embryos in a nonspecific way. Also, anti-Sry oligonucleotides did not influence sex determination in embryos, although there are several possible explanations for this.

The expression of the Spec1 gene of Strongylocentrotus purpuratus and its Lytechinus pictus homologue LpS1 was analyzed in reciprocal hybrid embryos of these two species of sea urchin. While the time course of accumulation of Spec1 mRNA was nearly normal in hybrid embryo populations, the accumulation of LpS1 mRNA was not. This was particularly evident in plutei, where the level of LpS1 mRNA was less than 5% that in normal L. pictus plutei. In situ hybridization analysis of serial sections indicated that LpS1 mRNA was detectable in only about 2% of hybrid plutei in either cross, whereas Spec1 mRNA was present in nearly all hybrid plutei; expression of either homologue was appropriately restricted to the aboral ectoderm. In crosses of L. pictus eggs with S. purpuratus sperm (LpSp), about 1% of hybrid plutei expressed LpS1 RNA in most or all aboral ectoderm cells at normal levels, and did not express Spec1 RNA; in another 1% of the LpSp hybrid plutei the Spec1 and LpS1 transcripts were present at normal levels in complementary, non-overlapping patches of contiguous aboral ectoderm cells. In the reciprocal SpLp cross, each hybrid pluteus expressed either only the LpS1 gene (about 2%) or only the Spec1 gene throughout the aboral ectoderm. In SpLp hybrid gastrulae the level of LpS1 mRNA was less restricted; about 2% of the embryos contained only LpS1 RNA, and about half expressed only Spec1 transcripts, but in the remaining embryos Spec1 and LpS1 transcripts were coexpressed in the same aboral ectoderm cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Amplification of sequences by the polymerase chain reaction (PCR) has become a powerful tool in the study of gene expression. The technique is, in fact, so powerful that it may detect 'leaky transcription'. Thus, it is now important to be able to quantify the transcripts that are amplified to determine whether or not they represent legitimate transcription of target genes. In this paper, we describe a one-step amplification reaction coupled to solution hybridization/RNase protection that is capable of quantitating specific transcripts in total RNA from one to ten preimplantation mouse embryos and is generally applicable to any cloned mRNA sequence.

Hybrid embryos were derived from reciprocal crosses of Strongylocentrotus purpuratus and Lytechinus pictus sea urchins. The expression of proteins specific for L. pictus was restricted in these hybrid embryos, while this was not so for most proteins specific for S. purpuratus. In particular, the aboral ectoderm-specific calcium-binding protein Spec1 was expressed at normal levels in hybrid embryos, but its L. pictus homologue, LpS1, was considerably reduced. LpS1 mRNA accumulated in hybrid plutei to only 4-5% of its normal level. Transcription of the LpS1 gene was substantially reduced in hybrid embryos, as determined by a nuclear RNA run-on assay. Southern blot analysis of genomic DNA indicated that there was no detectable loss or rearrangement of LpS1 DNA in hybrid embryos. Thus, the Spec1 gene is expressed normally in hybrid embryos, but the transcription of its homologue, the LpS1 gene, is considerably restricted.

One hundred forty-three patients with cutaneous T cell lymphoma were treated with topical carmustine (BCNU). A complete response was obtained in 86% of those with limited extent (less than 10%) plaques (T1 stage), in 48% of those with extensive (greater than or equal to 10%) plaques (T2 stage), and in 21% of those with erythroderma. The median time to achieve complete response was 11.5 weeks. Favorable results were obtained in patients with less than 5% involvement treated locally. Mild hematopoietic depression occurred in less than 10% of patients. Erythematous reactions were common, but no secondary cutaneous malignancies occurred. Differences in freedom from relapse or in survival between T2-stage patients with and those without clinical adenopathy were not statistically significant. The 5-year overall survival rate was 77%; the median survival time was 9.4 years.

A set of at least 11 actin genes has been isolated from genomic recombinant deoxyribonucleic acid libraries of the sea urchin Strongylocentrotus purpuratus. Most of the isolates derive from a library which represents the genome of a single animal. There are at least five distinct types of sea urchin actin gene, some of which are represented by multiple copies in the genome. The actin gene types are distinguished by nonhomologous flanking sequences and intervening sequences, though the protein coding sequences appear in most cases to be quite similar. Eight of the 11 genes isolated have been recovered in lambda recombinants that contain two actin genes, linked at 5- to 9-kilobase distances. Restriction map overlaps suggest that the genome contains an array of at least three of these genes spaced over about 30 kilobases of deoxyribonucleic acid. In the linkage patterns observed, actin genes of diverse types were linked to each other. In early embryos, actin messenger ribonucleic acid (RNA) transcripts of 1.8 and 2.2 kilobases were found, and the longer of these transcripts was more prevalent in the maternal RNA of the egg. From RNA gel blot experiments, we conclude that the two transcripts derive from different actin gene types. Different repetitive sequences were located to either side of most of the actin genes, and in most observed cases the repeat sequences which were adjacent to actin genes of a given type were similar. The repeat sequences flanking the actin genes belonged to families which were transcribed, but those repeats in the neighborhood of the actin genes which have been investigated were not themselves represented in the stable RNAs of eggs or early embryos.

The relative transcription of three unlinked actin genes of the sea urchin Strongylocentrotus purpuratus was measured in isolated nuclei, at several stages during embryonic development. Transcription of two cytoskeletal actin genes, CyI and CyIIIa, was first detected in 64-128 cell embryos. At the early stages, the CyIIIa gene is several-fold more active per embryo than CyI. The relative transcription of these two genes changes as development proceeds so that by the pluteus stage the CyI gene is at least twice as active per embryo as the CyIIIa gene. Both the time of initial detection of transcription of these two genes and the shift in their relative transcription during development correspond closely with the appearance and relative abundance in embryos of the mRNAs from these genes. Transcription of the muscle actin gene M was first detected in nuclei from pluteus stage embryos and thus also closely correlates with the first appearance of the muscle actin gene mRNA in embryos. The tight temporal coupling of the appearance in embryos of mRNA from these genes and the detection of their transcription in nuclei suggests that the regulation of their expression is in large part transcriptional. In addition to examining the transcription of these actin genes, we discovered that a member of an actively transcribed repeated sequence family is located upstream of the muscle actin-coding sequence. This sequence, which is present at least several hundred times within the genome and hybridizes strongly to RNA synthesized by RNA polymerase III at cleavage stages and to RNA synthesized in nuclei from pluteus stage embryos, shows little hybridization at blastula and gastrula stages.

A 46-year-old man presented with an unusual angiosarcoma of skin and urinary bladder, clinically suggestive of Kaposi's sarcoma (KS). Histologically, the pattern was that of an anaplastic angiosarcoma with only minimal regions considered characteristic of KS. It is suggested that this rare type of angiosarcoma may be closely related to, if not best classified as, an anaplastic variant of KS. The cutaneous lesions responded to intralesional vinblastine. The association of anaplastic angiosarcoma with homosexual sexual practices should be investigated along with those cases having the classical histologic characteristics of Kaposi's sarcoma.

The expression of three different actin genes in the sea urchin, Strongylocentrotus purpuratus, was monitored in embryos and adult tissues by using untranslated mRNA sequences as specific hybridization probes. Three distinct patterns of expression were found: muscle specific, embryo specific, and constitutive (i.e., present in all tissues examined). The actin genes encoding the muscle-specific and constitutively expressed genes were each found to be present once in the haploid genome. The embryo-specific probe could derive from either a single gene or a small subset of actin genes. These data demonstrate that at least three members of the sea urchin actin gene family are expressed in distinct ways and thus are probably associated with different regulatory programs of gene expression necessary for development of this metazoan.

We report the nucleotide sequence of the single muscle actin gene of the sea urchin Strongylocentrotus purpuratus. Comparison of the protein-coding sequence of this muscle actin gene (pSpG28) with that of two linked sea urchin cytoskeletal actin genes (pSpG17 and CyIIa) reveals a region of exceptional sequence conservation from codon 61 through codon 120. Furthermore, when silent nucleotide changes are compared, the conservation of this region is still evident (7.9% silent site differences in the conserved region vs 43.3% silent site differences in the rest of the gene when pSpG28 and CyIIa are compared), indicating that the conservation is not due to particularly stringent selection on the portion of the protein encoded by this region of the genes. These observations suggest that a gene conversion has occurred between the muscle actin gene and a cytoskeletal actin gene recently in the evolution of the sea urchin genome. Gene conversion between nonallelic actin genes may thus play a role in maintaining the homogeneity of this highly conserved gene family.

The accumulation of the mRNAs from four Strongylocentrotus purpuratus actin genes (the single muscle gene M, and three cytoskeletal genes CyI, CyIIIa, and CyIIIb) and of transcripts from an RNA polymerase III-transcribed repeated sequence family (SURF1) was followed throughout the early development of hybrid embryos of S. purpuratus and Lytechinus pictus. Each of the actin mRNAs appeared in hybrid embryos, constructed in either direction (Sp female X Lp male and Lp female X Sp male), at approximately the same time that they appear in normal S. purpuratus embryos. Transcripts of the repeated sequence family SURF1 also appeared at the correct time in the hybrid embryos, but were present at substantially reduced levels when contributed by the paternal genome (Lp female X Sp male). The accurate temporal expression of these genes indicates that both sets of hybrid embryos contain factors which regulate the timing of their transcription.

DNA-dependent RNA polymerase from Escherchia coli was used to transcribe chromatin from human leukocytes and purified human DNA. RNA was labeled at the 5' terminus with either [gamma-32P]ATP or [gamma-32P]GTP and internally with [3H]UTP. Determination of the average chain length of the RNA molecules by the ratio of moles of 3H-labeled nucleotide incorporated to moles 32P-labeled nucleotide incorporated showed that the size of the transcript of purified DNA was about 2 1/2 times greater than those from chromatin. The percentage of chains initiated with ATP and GTP was observed to vary with the template, the ATP to GTP ratio being greater on chromatin. The kinetics of 3H and 32P hybridization of transcripts of purified DNA showed hybridization primarily to nonrepetitive sequences. Transcripts from the chromatin templates when hybridized to DNA showed a larger proportion of RNase resistance of the 32P-termini at low Cot's.

Analysis of actin-coding RNAs in interspecific hybrid sea urchin embryos of Strongylocentrotus purpuratus and Lytechinus variegatus, and S. purpuratus and S. droebachienis has revealed the presence of transcripts from both paternal and maternal S. purpuratus actin gene alleles. In the L. variegatus female X S. purpuratus male embryos transcripts from at least two different paternal actin gene alleles are present in both the blastula and prism stages. In the reciprocal S. purpuratus female X L. variegatus male embryos, the same two maternal (S. purpuratus) alleles were also expressed as RNA in blastula. The S. droebachiensis female X S. purpuratus male embryos appear to contain transcripts from at least one paternal actin gene allele at the blastula stage. The paternally derived actin-coding RNAs are the same size as the mature actin mRNAs expressed in normal S. purpuratus embryos. Since all known S. purpuratus actin genes contain at least two introns, the paternal alleles are not only transcribed in the hybrid embryos, but also the primary transcripts are probably processed to mature mRNA. An explanation of the diversity of observations in the literature on paternal genome expression in hybrid sea urchin embryos is discussed.

We have determined the complete nucleotide sequence of a sea urchin actin gene, including the entire protein-coding sequence, introns and approximately 500 and 700 nucleotides adjacent to protein-coding-sequence on the 5' and 3' sides, respectively. This gene is split between codons 121 and 122 and within codon 204 by two introns which are 233 and 181 nucleotides in length, respectively. Comparison of the sequence of the two introns indicates a region of distant relatedness which covers about 25% of their lengths, suggesting that these sequences might have derived from a common ancestral sequence. The encoded amino acid sequence, which matches plasmic-like than muscle-like when compared to vertebrate actins. Analysis of the coding-flanking regions indicates the presence of sequences similar to those thought to be important for initiation of transcription and polyadenylation of mRNA. The location of these sequences and the size of an actin mRNA, transcribed from this or a very closely related gene, suggests that initiation occurs 347 nucleotides 5' of coding and polyadenylation approximately 515 nucleotides 3' of coding.

The distribution of total polyadenylated RNA and mRNAs from the beta-actin, fibronectin, and cytokeratin Endo A genes was examined in preimplantation mouse embryos using in situ hybridization of riboprobes to RNA in sections of embryos. Polyadenylated RNA was found in the cytoplasm of all cells of blastocyst-stage embryos, whereas the specific mRNAs displayed three distinct patterns of expression: uniform throughout the embryo (beta-actin), enriched in the inner cell mass (fibronectin), and enriched in the trophectoderm (Endo A). In eight-cell embryos, the polyadenylated RNA was more concentrated in nuclei than in the cytoplasm (as noted previously), although this was not the case in blastocysts, nor was it true for the specific mRNAs that were examined. These experiments demonstrate that there is localized gene expression in the early mouse embryo, which correlates with the formation of the trophectoderm and the inner cell mass.

A sensitive search has been made in Drosophila melanogaster DNA for short repetitive sequences interspersed with single copy sequences. Five kinds of measurements all yield the conclusion that there are few short repetitive sequences in this genome: () Comparison of the kinetics of reassociation of short (360 nucleotide) and long (1,830 nucleotide) fragments of DNA; 2) reassociation kinetics of long fragments (2,200 nucleotide) with an excess of short (390 short nucleotide) fragments; 3) measurement of the size of S1 nuclease resistant reassociated repeated sequences; 4) measurement of the hyperchromicity of reassociated repetive fragments as a function of length; 5) direct assay by kinetics of reassociation of the amount of single copy sequence present on 1,200 nucletodie long fragments which also contain repetitive sequences.

The cell-specific expression of three actin genes from the sea urchin species Strongylocentrotus purpuratus was examined in hybrid embryos of S. purpuratus and another species, Lytechinus pictus, by in situ hybridization. The mRNAs from each of these genes displayed distinct spatial patterns of expression in late-stage hybrid embryos (constructed in either direction), being detected only in the cell lineages where they are normally found in S. purpuratus embryos (i.e. CyIIIa, only in the aboral ectoderm lineage; CyI, in the gut, oral ectoderm and some mesenchyme cells of plutei, and preferentially in the archenteron of gastrulae; M, only in two small clusters of cells near the esophagus in plutei). These results, together with our previous observation that expression of each of these genes is activated at the same stage in these hybrid embryos as in normal S. purpuratus embryos, demonstrate that the trans-acting factors which are necessary to regulate both the temporal and spatial expression of these genes are present in the hybrid embryos. Previous experiments have shown that the expression of a chimeric gene containing the CyIIIa promoter fused to a bacterial chloramphenicol actetyltransferase (CAT) gene is not confined to the correct cell lineage (aboral ectoderm) when injected into Lytechinus embryos. The conclusion from these sets of data is that the factor(s) that regulate the spatial expression of at least one of the actin genes must derive from transcription of the zygotic genome.

Seven patients with lymphomatoid papulosis were treated with solutions of topical carmustine, a nitrosourea compound. Recently used schedules have employed 10 mg of carmustine in dilute alcohol applied to the total skin surface daily for four to 17 weeks (total dosage, 280 to 1,180 mg). All patients experienced a rapid reduction in the number and size of lesions. Maintenance therapy consisted of local applications of carmustine (2 to 4 mg/mL of 95% ethanol) to individual new papules. This method was effective in suppressing disease activity and reduced by half the average life cycle of individual lesions. However, long-term lesion-free remissions were not seen. Bone marrow depression did not occur.

A large fraction of the genome of the lepidopteran Antheraea pernyi consists of interspersed single-copy sequences and repetitive DNA sequences of 300 nucleotide average length. Most of the single-copy sequences are about 800 nucleotides long and a minority are considerably longer. Thus, the organization of the DNA sequences of this insect is similar to that of most higher organisms and different from that of Drosophila.

The progress that has been made in the last several years toward an understanding of the expression of the actin genes of the sea urchin is impressive. It serves as an excellent example of how the application of modern molecular biological techniques to a classic experimental system (the sea urchin embryo) can begin to give us insight into the processes of embryological development. There is reason to hope that general principles will emerge from studies such as these, but many questions are unanswered. With specific regard to the actin genes and proteins, there are some obvious questions. Are the actins encoded by the different genes functionally distinct, and what roles do they play in differentiation and development? How is the expression of each of these genes regulated; i.e., what molecules participate, how do they work, where are they located in the embryo, and when do they appear? The more general question is: How are these (and other) genes and proteins affected by, or how do they contribute to, determination and induction in early development? We hope that answers to the specific questions posed will provide important steps toward answers to the general question.

We have examined the organization of the repeated and single copy DNA sequences in the genomes of two insects, the honeybee (Apis mellifera) and the housefly (Musca domestica). Analysis of the reassociation kinetics of honeybee DNA fragments 330 and 2,200 nucleotides long shows that approximately 90% of both size fragments is composed entirely of non-repeated sequences. Thus honeybee DNA contains few or no repeated sequences interspersed with nonrepeated sequences at a distance of less than a few thousand nucleotides. On the other hand, the reassociation kinetics of housefly DNA fragments 250 and 2,000 nucleotides long indicates that less than 15% of the longer fragments are composed entirely of single copy sequences. A large fraction of the housefly DNA therefore contains repeated sequences spaced less than a few thousand nucleotides apart. Reassociated repetitive DNA from the housefly was treated with S1 nuclease and sized on agarose A-50. The S1 resistant sequences have a bimodal distribution of lengths. Thirty-three percent is greater than 1,500 nucleotide pairs, and 67% has an average size about 300 nucleotide pairs. The genome of the housefly appears to have at least 70% of its DNA arranged as short repeats interspersed with single copy sequences in a pattern qualitatively similar to that of most eukaryotic genomes.

An examination of the size and relative abundance of actin-coding RNA in embryos of four sea urchins (Strongylocentrotus purpuratus, Strongylocentrotus droebachiensis, Arbacia punctulata, Lytechinus variegatus) and one sand dollar (Echinarachnius parma) reveals a generally conserved program of expression. In each species the relative abundance of these sequences is low in early embryos and begins to rise during late cleavage or blastula stages. In the four sea urchins, actin-coding RNAs increase between approximately 9- and 35-fold by pluteus or an earlier stage, and in the sand dollar about 5.5-fold by blastula. A major actin-coding RNA class of 2.0-2.2 kilobases (kb) is found in each species. A smaller actin-coding RNA class, which accumulates during embryogenesis, is also present in S. purpuratus (1.8 kb), S. droebachiensis (1.9 kb), and A. punctulata (1.6 kb), but apparently absent in L. variegatus and E. parma. In S. droebachiensis, actin-coding RNA is relatively abundant in unfertilized eggs and drops sharply by the 16-cell stage. This is in contrast to the other sea urchins where the actin message content is relatively low in eggs and does not change substantially in the embryos throughout early cleavage. The observations in this study suggest that the pattern of embryonic expression of at least some members of this gene family is ancient and conserved.

Quantitative electron microscopy can provide objective measurements of nuclear atypia in lymphoid cells in skin biopsies during early stages of infiltration of the skin as part of inflammatory or neoplastic processes. This potentially provides a method for establishing reproducible criteria for determining whether an individual skin biopsy represents mycosis fungoides or is unlikely to represent mycosis fungoides. To investigate such criteria, quantitative electron microscopic studies of skin biopsies from 109 patients were performed. Seventy-seven patients had benign disorders, 16 patients had early mycosis fungoides, and 16 patients had controversial lesions. Measurements were made of lymphocyte nuclear profile perimeter and areas in electron micrographs. A nuclear contour index was calculated. On the basis of the mean degree of nuclear convolution alone, mycosis fungoides was not adequately distinguished from benign disorders. Better discrimination was achieved when the proportion of cells with a anuclear contour index of 9.0 or more was considered as an additional actor. When statistical methods were used to select discriminating factors, the best electron microscopic discrimination between benign and mycosis fungoides groups occurred when the proportion of cells with a nuclear contour index of 7 or more and the proportion of cells with a nuclear profile area greater than 30 sq. micrometer. were used together. Nomograms are presented which demonstrate the use of these criteria for a given case.

The arrangement of repetitive and non-repetitive sequence was studied in the genomic DNA of the oyster (Crassostrea virginica), the surf clam (Spisula solidissima), the horseshoe crab (Limulus polyphemus), a nemertean worm (Cerebratulus lacteus) and a jelly-fish (Aurelia aurita). Except for the jellyfish these animals belong to the protostomial branch of animal evolution, for which little information regarding DNA sequence organization has previously been available. The reassociation kinetics of short (250-300 nucleotide) and long (2,000-3,000 nucleotide) DNA fragments was studied by the hydroxyapatite method. It was shown that in each case a major fraction of the DNA consists of single copy sequences less than about 3,000 nucleotides in length, interspersed with short repetitive sequences. The lengths of the repetitive sequences were estimated by optical hyperchromicity and S1 nuclease measurements made on renaturation products. All the genomes studied include a prominent fraction of interspersed repetitive sequences about 300 nucleotides in length, as well as longer repetitive sequence regions.

Quantitative electron microscopy was used to measure lymphocyte nuclear contours in skin biopsies from 109 patients, 77 with benign disorders, 16 with early mycosis fungoides (MF), and 16 with controversial lesions. A nuclear contour index (NCI) was calculated on electron micrographs by dividing the nuclear profile circumference by the square root of the nuclear area. Significant differences were found between the group mean NCI for MF (NCI = 6.1 +/- 0.1) and for the benign group (NCI = 4.6 to 5.4 +/- 0.1; P less than 0.005). The group mean NCI for the controversial cases was significantly lower than that of the MF group (P less than 0.05). It is suggested that a definite electron microscopic diagnosis of MF requires first a patient mean NCI of 6.1 or more, and second, at least 6% of lymphocytes with an NCI of 9 or more. These criteria give a false positive rate of 3% in benign and controversial disorders and a 50% false negative rate for early MF. Only lymphocytes with an NCI of 16 or more appear specific for MF (or Sezary's syndrome), but are not found in all cases.

Southern transfer and solution hybridization experiments, using as probe a DNA fragment that encodes for Drosophila actin, demonstrate cross hybridization to DNA from the sea urchin Strongylocentrotus purpuratus. Recombinant DNA clones that contained sea urchin genomic DNA fragments were constructed and screened for the presence of actin-encoding DNA sequences by colony hybridization with the Drosophila actin sequence. Two different putative actin-encoding clones were identified and were shown to specifically hybridize actin-encoding mRNA from a complex mRNA population. Southern blot hybridization experiments with both the Drosophila actin sequence and one of the cloned sea urchin sequences, in conjunction with solution hybridization data, suggest an actin gene copy number of 5-20 per haploid genome. DNA sequence analysis of one of the cloned sequences indicates that this fragment codes for a cytoplasmic form of actin and contains an intervening sequence of at least 200 nucleotides beginning immediately after amino acid 121 in the protein sequence.

A 69-year-old man had reversible generalized thinning of the scalp hair and normal-appearing scalp skin that proved to be secondary to follicular mucinosis. This case illustrates that when mild degrees of follicular degeneration and inflammation occur in this disorder, physical findings other than alopecia may be absent. In rare instances, follicular mucinosis can occur as a chronic diffuse noncicatricial alopecia.

We show that the synthesis of actin is regulated developmentally during early sea urchin embryogenesis and that the level of synthesis of this protein parallels the steady-state amounts of the actin messenger ribonucleic acids (RNA). An in vitro translation and RNA blotting analysis of embryo RNA from several stages of early development indicated that during the first 8 h after fertilization there was a low and relatively constant level of actin messenger RNA in the embryo. Between 8 and 13 h of development, the amount of actin messenger RNA began to increase both in the cytoplasm and on polysomes, and by 18 h the amounts of actin message per embryo had risen between approximately 10- and 25-fold in the cytoplasm and between 15- and 40-fold on polysomes. Two size classes of actin messenger RNA (2.2 and 1.8 kilobases) were identified in unfertilized eggs and in all of the developmental stages examined. The amount of each actin message class increased over a similar time interval during early development. However, the amounts of these size classes in the cytoplasm relative to each other shifted between the earliest stages examined (2 to 5 h) and the hatching blastula stage (18 h), with the ratio of the 1.8-kilobase actin messenger RNA to the 2.2-kilobase actin messenger RNA increasing almost threefold during this period.

A repeated sequence element which is located about 200 nucleotides upstream from the protein-coding portion of the muscle actin gene (probably within a large 5' intron) in the genome of the sea urchin, Strongylocentrotus purpuratus has been characterized, and shown to contain the sequence features which indicate that it has been transposed by means of an RNA intermediate. This retroposon-like sequence, SURF1-1, is a member of a family which is dispersed and repeated about 800 times in the genome, referred to as SURF1 (sea urchin retroposon family 1). In vitro transcription of this sequence by RNA polymerase III defines a 300 nucleotide transcription unit which is bounded by a short direct repeated sequence. The 3' end of this unit contains a simple 21 nucleotide A+T-rich sequence characteristic of retroponons, and a consensus B box portion of an internal RNA polymerase III promotor is located 60 to 80 nucleotides downstream from the two sites of transcription initiation. This sequence also contains a 40 nucleotide region that is related to several tRNA sequences (containing the B box), and a 79 nucleotide sequence which is homologous to a repeated sequence previously shown to be present within the 3' untranslated portions of the Spec1 and Spec2 mRNAs of this species (1). Analysis of transcripts of this sequence family in RNA from several embryonic stages indicates that its expression is highest at 11 hours postfertilization (about 128 cells) and drops as development proceeds. Furthermore, most or all, transcription of this sequence family in nuclei isolated from 11 hour embryos is by RNA polymerase III, and is from the same strand which is transcribed in vitro.

A 10-year experience in eighty-six patients confirms the effectiveness of topical carmustine (BCNU) in mycosis fungoides (MF). Complete remission (CR) was achieved in 84% of those with less than 10% involvement (stage IA), median CR, 12 months, and in 52% with greater than 10% involvement (stage IB), median CR, 23 months. The probability of freedom from relapse for 1 year was 72% in stage IA and 37% in stage IB. No deaths in stages IA or IB were attributable to MF. Including all causes of death, the probability of 5-year survival for stage IA was 93% and for stage IB, 48%. Good results were obtained with only local BCNU in fourteen patients with mostly less than 5% involvement. Five of seven with poikilodermatous MF, two with parapsoriasis en plaques (PEP), and three with lymphomatoid papulosis did well. Persistent local therapy cleared deeply infiltrated lesions in some patients. With present schedules, the hazard of bone marrow depression is slight. Erythematous reactions and telangiectasia are troublesome but have not been accompanied by premalignant changes.

RNA complementary to bulk humanplacental DNA was synthesized in vitro both in the presence and absence of (3)H-labeled ribonucleotides. The (3)H-labeled RNA was used directly for hybridization to the DNA of human metaphase chromosomes, whereas the unlabeled complementary RNA was labeled chemically with (125)I before hybridization. A comparison of autoradiographs produced by either isotope revealed no qualitative differences in the chromosomal annealing sites of the same population of RNA molecules. Since (125)I-labeled nucleic acids give similar, if not identical, results as do (3)H-labeled nucleic acids in in situ hybridization experiments, their use should make possible the localization of genetic elements for which tritium labeling methods are either inadequate or not possible.