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Determining the extent of genetic variation that reflects local adaptation in crop-wild relatives is of interest for the purpose of identifying useful genetic diversity for plant breeding. We investigated the association of genomic variation with geographical and environmental factors in wild barley (Hordeum vulgare L. ssp. spontaneum) populations of the Southern Levant using genotyping by sequencing (GBS) of 244 accessions in the Barley 1K+ collection. The inference of population structure resulted in four genetic clusters that corresponded to eco-geographical habitats and a significant association between lower gene flow rates and geographical barriers, e.g. the Judaean Mountains and the Sea of Galilee. Redundancy analysis (RDA) revealed that spatial autocorrelation explained 45% and environmental variables explained 15% of total genomic variation. Only 4.5% of genomic variation was solely attributed to environmental variation if the component confounded with spatial autocorrelation was excluded. A synthetic environmental variable combining latitude, solar radiation, and accumulated precipitation explained the highest proportion of genomic variation (3.9%). When conditioned on population structure, soil water capacity was the most important environmental variable explaining 1.18% of genomic variation. Genome scans with outlier analysis and genome-environment association studies were conducted to identify adaptation signatures. RDA and outlier methods jointly detected selection signatures in the pericentromeric regions, which have reduced recombination, of the chromosomes 3H, 4H, and 5H. However, selection signatures mostly disappeared after correction for population structure. In conclusion, adaptation to the highly diverse environments of the Southern Levant over short geographical ranges had a limited effect on the genomic diversity of wild barley. This highlighted the importance of nonselective forces in genetic differentiation.

After domestication, during a process of widespread range extension, barley adapted to a broad spectrum of agricultural environments. To explore how the barley genome responded to the environmental challenges it encountered, we sequenced the exomes of a collection of 267 georeferenced landraces and wild accessions. A combination of genome-wide analyses showed that patterns of variation have been strongly shaped by geography and that variant-by-environment associations for individual genes are prominent in our data set. We observed significant correlations of days to heading (flowering) and height with seasonal temperature and dryness variables in common garden experiments, suggesting that these traits were major drivers of environmental adaptation in the sampled germplasm. A detailed analysis of known flowering-associated genes showed that many contain extensive sequence variation and that patterns of single- and multiple-gene haplotypes exhibit strong geographical structuring. This variation appears to have substantially contributed to range-wide ecogeographical adaptation, but many factors key to regional success remain unidentified.

The notion of species as reproductively isolated units related through a bifurcating tree implies that gene trees should generally agree with the species tree and that sister taxa should not share polymorphisms unless they diverged recently and should be equally closely related to outgroups. It is now possible to evaluate this model systematically. We sequenced multiple individuals from 27 described taxa representing the entire Arabidopsis genus. Cluster analysis identified seven groups, corresponding to described species that capture the structure of the genus. However, at the level of gene trees, only the separation of Arabidopsis thaliana from the remaining species was universally supported, and, overall, the amount of shared polymorphism demonstrated that reproductive isolation was considerably more recent than the estimated divergence times. We uncovered multiple cases of past gene flow that contradict a bifurcating species tree. Finally, we showed that the pattern of divergence differs between gene ontologies, suggesting a role for selection.

Abstract:Accumulation by dispossession (ABD) is deeply implicated in the broad history of tourism development at Luxor, Egypt. ABD informs a theme of loss found in ethnographic, historical and archival sources in three significant periods of tourism development: the formative period of tourism extending to the mid-18th century, the following mass tourism era and the post-1970s period. Dispossessions including the absence of consent, violent appropriations, monopolistic practices, repeated displacements and the policing of space belie the discourse of tourism as exchange or economic development and reveal differently scaled dimensions of the exercise of power and hierarchy.Résumé:L’accumulation par dépossession (APD) est profondément ancrée dans une histoire générale du développement du tourisme à Louxor, en Égypte. L’APD relève du thème de la perte que l’on retrouve dans des sources ethnographiques, historiques et archivistiques durant trois périodes significatives : la période formative du tourisme, qui s’étend jusqu’à la moitié du dix-huitième siècle ; celle du tourisme de masse ; puis, la période qui succède aux années 1970. Des dépossessions découlant de l’absence de consentement, de violentes appropriations, de pratiques monopolistiques, de déplacements répétés et de la réglementation de l’espace démentent le discours du tourisme comme échange ou comme développement économique. De plus, ces dépossessions révèlent des dimensions stratifiées de l’exercice du pouvoir, voire de la hiérarchie.

A system for the course control and spatial stabilization of the output beam of a femtosecond laser system is realized. An accuracy of 0.5 µrad is achieved long term in a laboratory environment for a beam with an initially daily deviation of more than 40 µrad. The application and importance of the method is illustrated for laser pulse shortening in a hollow waveguide resulting in a stable output power and an 8 fs pulse duration for more than 10 h operation time.

Assembly of mitochondrial F1‐ATPase in Saccharomyces cerevisiaerequires the molecular chaperone, Atp11p. Database searches have identified protein sequences from Schizosaccharomyces pombeand two species of Drosophilathat are homologous to S. cerevisiaeAtp11p. A cDNA encoding the putative Atp11p from Drosophila yakubawas shown to complement the respiratory deficient phenotype of yeast harboring an atp11::HIS3disruption allele. Furthermore, the product of this Drosophilagene was shown to interact with the S. cerevisiaeF1β subunit in the yeast two‐hybrid assay. These results indicate that Atp11p function is conserved in higher eukaryotes.

Abstract.: The flour beetle Tribolium castaneum has become an important model organism for comparative studies of insect development. Many developmentally important genes have now been cloned from both Tribolium and Drosophila and their expression characteristics were studied. We analyze here the complete coding sequences of 17 homologous gene pairs from D. melanogaster and T. castaneum, most of which encode transcription factors. We find that the Tribolium genes are on average 30% shorter than their Drosophila homologues. This appears to be due largely to the almost-complete absence of trinucleotide repeats in the coding sequences of Tribolium as well as the generally lower degree of internal repetitiveness. Clusters of polar and other amino acids such as glutamine, proline, and serine, which are often considered to be important for transcriptional activation domains in Drosophila, are almost completely absent in Tribolium. Codon usage is generally less biased in Tribolium, although we find a similar tendency for the preference of G- or C-ending codons and a higher bias in conserved subregions of the proteins as in Drosophila. Most of the aminoacid substitutions in the DNA-binding domains of the transcription factors occur at residues that do not make a specific contact to DNA, suggesting that the recognition sequences are likely to be conserved between the two species.

Immunoregulatory α-globulin (IRA), a naturally occurring immunosuppressive peptide isolated from pooled normal human plasma, was administered to Lewis rats before allografting of LBNF1kidneys. Control Lewis rats received either no treatment or inactive human peptide before kidney allografting. Median survival was 10.0 ± 2.2 (SD) days and 9.0 ± 1.0 days in Lewis rats receiving inactive peptide or no treatment, and 21.0 ± 1.9 days in Lewis recipients treated with IRA, P < 0.05. Three IRA-treated recipients were long-term survivors. At a time when the direct immunosuppressive effect of IRA was long absent, the serum of the long-term survivors could block the killing of LBNF1target kidney cells by lymphocytes from immune Lewis animals.

The vasodilator, hypotensive, and antihypertensive effects of hydralazine and its known and putative metabolites were compared in vitro, in the isolated, perfused mesenteric arterial bed of the rat, and in vivo, in the urethane-anesthetized normotensive rat (NR) and in the conscious renal hypertensive rat (RHR). In the mesenteric bed, hydralazine produced inhibition of noradrenaline (NA)-induced vasoconstriction (IC50–NA 0.4 μg/ml). All the metabolites were five to >250 times less potent than the parent compound. Hydralazine inhibited potassium-induced vasoconstriction at concentrations (IC50–K700 μg/ml) above those required to inhibit NA. Two metabolites, 9-hydroxy-3-methyl-s-triazolo-(3.4-a)phthalazine and the acetone hydrazone (HP-AH), were more potent (five- and 10-fold, respectively) than hydralazine in inhibiting potassium-induced vasoconstriction. The other metabolites produced <50 inhibition at the highest concentration tested. In in vivo studies, blood pressure in NR or RHR was reduced by hydralazine, following doses of 0.1 or 0.25 mg/kg i.v. and above. HP-AH was sixfold less active than hydralazine in NR and 10-fold less active in RHR, while the pyruvic acid hydrazone was 33- and 14-fold less active, respectively. The other metabolites tested were practically inactive in concentrations up to the limits of solubility. Although several hydralazine metabolites show some vasodilator and blood pressure–lowering activity, it seems unlikely that the formation of metabolites is a major factor in the antihypertensive effect of hydralazine or is responsible for its long duration of action.

Summary: A method is described for the quantitative analysis of the nerve-growth-promoting activity of biological molecules in tissue culture. The criteria used for the evaluation of this activity is based on the neurite length as well as the total number of neurites produced by the explant of whole dorsal root ganglia from 12-d-old chick embryos. A nerve growth index (NGI) is given to each ganglion during each of a 5-d culture period. The NGI is defined as the product of average neurite length in millimeters and the total number of neurites. We report that with increasing concentrations of fetal bovine serum, there was a proportional increase in NGI due to increased neurite density while the neurite length was not greatly affected. The NGI of several proteins with known nerve growth promoting activity, namely nerve growth factor, insulin, transferrin, and fibronectin were investigated for their activity and compared with that of fetal bovine serum.

The use of a single, commercially available column packing, TabsorbR, is described for the g. l. c. separation of a large number of different compounds. The resolution of the homologous members of the following series of compounds was achieved: (1) saturated fatty acids (C1-C18), (2) normal aliphatic saturated dlcarboxylic acids (C2-C14), (3) normal aliphatic saturated alcohols (C1-C24), (4) normal aliphatic saturated amines (C1C12), (5) the common amino acids except arginlne, histidlne and cysteine, (6) aliphatic hydrocarbons (C10-C20) and (7) monosaccharides. It should be noted that twenty-two monosaccharides including three hexosamines and two anhydrohexoses, could be resolved as aldltol acetates In a single run. In addition, galacturonic, glucuronic and lduronlc acids could be separated from one another as their 1, 4-lactones. The resolution achieved in these series of compounds was found to be consistent and highly reproducible. It is of further interest that certain Isomers of the higher fatty acids and hydrocarbons with one double bond could also be separated from the normal and saturated compounds, respectively. The applicability of "Tabsorb" for the g. l. c. separation, although noted above to be considerably broad, is by far not yet exhausted. These procedures which form the basis for the quantitative determinations of the various compounds studied as demonstrated by analysis of glycopeptldes for neutral hexoses and proteins for the amino acids, can readily be adapted to preparative methods. From the biochemical point of view "Tab-sorb" is an extremely versatile column packing in that it can be used for the identification of many of the common building blocks of natural products.

Summary: Two new forms of BRP-2, a previously described bone resorptive protein, were purified from ascites fluids obtained from patients with hypercalcemia and metastatic bone cancer. The apparent molecular weights of BRP-2 and of these two proteins were 52,000, 48,000, and 46,000, respectively, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The three proteins have essentially the same amino acid compositions but differ with respect to their carbohydrate moieties. The amino-terminal amino acid sequences of the three glycoproteins were identical to each other as well as to human serum α2HS-(human serum) glycoprotein. The relationship of the three forms of BRP-2 to α2HS was also established immunochemically. The ascites proteins, as well as α2HS, on a molar basis, were approximately one-tenth as potent as bovine parathyroid hormone fragment (1–34) in their abilities to stimulate calcium release from bonein vitro. This study describes for the first time a possible function for human serum α2HS.

The success of the genetic approach to developmental biology has provided us with a suite of genes that are involved in the regulation of ontogenetic pathways. It is therefore time to ask whether and how such genes may be involved in the generation of adaptive phenotypes. Unfortunately, the current results do not provide a clear answer. Most of the genes that have been studied by developmental biologists affect early embryonic traits with major effects on the whole organism. These genes are often highly conserved which allows us to do comparative studies even across phyla. However, whether the same genes are also involved in short–term ecological adaptations remains unclear. The suggestion that early acting ontogenetic genes may also affect late phenotypes comes from the genetic analysis of quantitative traits like bristle numbers in Drosophila. A rough mapping of the major loci affecting these traits shows that these loci might correspond to well known early acting genes. On the other hand, there are also many minor effect loci that are as yet uncharacterized. We suggest that these minor loci might correspond to a different class of genes. In comparative studies of randomly drawn cDNAs from Drosophilawe find that there is a large group of genes that evolve fast and that are significantly under–represented in normal genetic screens. We speculate that these genes might provide a large, as yet poorly understood, reservoir of genes that might be involved in the evolution of quantitative traits and short–term adaptations.

α1T-glycoprotein (α1T) was isolated from normal human plasma in the immunochemically homogeneous state. The partial amino acid sequence and carbohydrate chains of this glycoprotein were determined. To achieve this, the carboxymethylated α1T was analyzed by sequencing some of the lysylendoprotease, V8 protease, tryptic, and cyanogen bromide peptides as well as the N-terminal sequence of the protein. A large number of amino acid residues (460 amino acids) was determined by chemical procedure. The peptide sequences were compared with that of other proteins. A high degree of homology was found for proteins of the albumin family. Further, human α-albumin, a new member of this protein family, showed an amino acid sequence identical to that of α1T indicating that these two proteins are very similar in amino acid sequence and composition. These proteins are closely related to α-fetoprotein; however, five carbohydrate chains were found on α1T at Asn12, Asn88, Asn362, Asn381, and Asn467 as biantennary complex type chains and the chain on Asn362 possessed a rare consensus sequence of Asn-X-Cys. Thus, α1T distinguishes itself by possessing five N-glycans, a finding reported here for the first time for the ALB family.

Beta-microseminoprotein (β-MSP), a sperm-coating antigen isolated from human seminal plasma, has apparent structural identity with “β-inhibin” isolated from the same source. Publication of the amino acid sequence of β-MSP revealed a greater than 96% homology with “β-inhibin,” with only a proline-threonine substitution at positions 39 and 40, and the omission of a glycine at position 93. Due to the nearly identical sequences of “β-inhibin” and β-MSP, we examined the ability of β-MSP and its tryptic peptides to inhibit basal follicle-stimulating hormone (FSH) secretion from rat pituitary cells in culture, the inhibin bioassay. Whole pituitaries collected from 250- to 300-g male rats were dispersed enzymatically and plated onto 24-well culture dishes for 3 days. β-MSP and its tryptic peptides were dissolved in cell culture medium, applied to the pituitary monolayer cell cultures, and incubated for an additional 3 days. FSH levels in the medium were determined by radioimmunoassay. A partially purified preparation of inhibin and our in-house inhibin standard, both prepared from porcine follicular fluid (pFFl), were included in the same assay. Whereas the partially purified inhibin from pFFl showed a dose-dependent inhibition of FSH secretion, with a 50% inhibitory dose (ID50) of 50 ng, which paralleled that of the standard, β-MSP and its tryptic peptides failed to depress FSH levels in the medium at any of the doses tested (10–10,000 ng/ml). We conclude that β-MSP is not an inhibin under our assay conditions.

Carbohydrate residues contribute to the hormone recognition site of the receptors for several hormones including insulin and TSH. The present studies were undertaken to ascertain whether glucose, mannose, or N-acetylglucosamine residues contributed to the FSH receptor recognition site. Initial studies revealed that the enriched FSH plasma membrane fraction contained less than 1% sialic acid and neutral hexoses.A partially purified enriched FSH plasma membrane binding fraction was prepared from Leydig cell-depleted calf testis by differential and sucrose density gradient centrifugation. Specific [125I]-FSH binding to the enriched FSH binding fraction was unaffected by graded concentrations (0.1 to 50 μg) of either concanavalin A or wheat germ agglutinin. In one study, the enriched FSH plasma membrane binding fraction was solubilized with 1% Triton X-100 and percolated through either a Concanavalin A-Sepharose 48 or a wheat germ agglutinin Sepharose column. When unbound and 0.2 M α-D-methylglucosylpyranoside (MEG) or N-acetylglucosamine (NAG)-eluted fractions were analyzed for specific [125I]-FSH binding, only the unbound fractions displayed specific binding. Specific FSH binding to its receptor was unaffected by 0.2 M MEG or 0.1 M NAG. When the preformed [125I]-FSH-receptor complex was solubilized with 1% Triton X-100 and percolated through a Concanavalin A-Sepharose 48 column, more than 90% of the preformed complex was retained on the column, but was eluted with 0.2 M MEG. Binding of the hormone-receptor complex was the result of binding of the lectin to the carbohydrate residues of the hormone, which do not appear to be necessary for direct hormone-receptor interaction.The results of these studies strongly suggest that neither mannose, glucose, nor N-acetylglucosamine residues constitute an intrinsic part of the FSH receptor binding site. Alternatively, if those residues are an intrinsic part of the FSH receptor, they are inaccessible to lectin binding. Although these three sugar residues may contribute to the conformation of the FSH molecule, they do not appear to be requisite for directly interacting with the receptor binding site of FSH.

These studies demonstrate that IRA will suppress both primary and secondary immune responses as measured by a hemolytic plaque assay. Suppression of the secondary response occurs whether IRA is administered prior to the immunizing injection of antigen or prior to the challenge injection of antigen. The fact that IRA administered at the time of initial antigen exposure was able to inhibit the response to a second, or challenge, dose of that antigen; and that the secondary response was significantly less than a normal primary response suggests that IRA administered at the time of initial antigen exposure confers partial tolerance to that antigen.

The Cuvierian tubules of Holothuria forskali Della Chiaje, a sea cucumber found in the Adriatic Sea, were investigated with regard to their carbohydrate moieties. From a Pronase digest of these tubules three types of carbohydrate units were isolated and characterized. 1. A high-molecular-weight glycopeptide fraction was shown to contain sulphated polyfucose, galactosamine, a uronic acid and a previously unknown neuraminic acid derivative. The sulphate was shown by i.r. analysis to be present as an O-ester. The carbohydrate unit was linked O-glycosidically to threonine and serine residues in the polypeptide chain. The hitherto unknown neuraminic acid derivative (Hf-neuraminic acid) was resistant to enzymic cleavage by neuraminidase, even after mild alkaline hydrolysis for the removal of O-acyl residues. However, the glycosidic linkage of this compound to the other part of the carbohydrate moiety was readily cleaved by mild acid hydrolysis. Its chromatographic properties distinguished Hf-neuraminic acid from other known neuraminic acid derivatives (N-acetyl-, NO-diacetyl-, NOO-triacetyl- and N-glycollyl-neuraminic acid). Further, this acidic sugar was shown to possess neuraminic acid as its basic structure. Thus, an as yet unknown substituent lends the distinct properties to Hf-neuraminic acid. 2. The carbohydrate composition of a second glycopeptide fraction consisting of a derivative of neuraminic acid, galactose, mannose and glucosamine was similar to that of the well-known carbohydrate groups of the globular glycoproteins. 3. The third fraction contained two glycopeptides containing the disaccharide, glucosylgalactose, which was shown to be linked to the hydroxyl group of hydroxylysine residues of a collagen-like protein. Approximately half of these residues were glycosylated. In addition to these glycopeptides, a small amount of a third glycopeptide that carried only a galactosyl residue was detected. The amino acid sequence of the two major compounds were found to be Gly-Ala-Hyl*-Gly-Ser and Gly-Pro-Hyl*-Gly-Asp, where Hyl* represents a glycosylated amino acid residue.

A new procedure for the qualitative and quantitative determination of asparagine, glutamine and pyrrolidonecarboxylic acid in total enzymic hydrolysates of peptides and glycopeptides based on g.l.c. has been developed. Under the conditions of esterification and trifluoroacetylation N-trifluoroacetylaspartic acid mono-n-butyl ester was formed from asparagine and N-trifluoroacetylglutamic acid mono-n-butyl ester from both glutamine and pyrrolidonecarboxylic acid. To distinguish between the latter two compounds, the esterification was carried out at room temperature yielding 30% of esterified pyrrolidonecarboxylic acid but less than 1% of esterified glutamine. In extending the g.l.c. of amino acids, the previously unknown positions in the g.l.c. elution pattern of the following amino acids could also be reproducibly determined: carboxymethylcysteine, homoserine, hydroxylysine and ∈-methyl-lysine. Further, certain glycopeptides were investigated and the artifacts due to their carbohydrate moieties were determined.