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Anthocyanin and blueberry intakes positively associated with cognitive function in population-based studies and cognitive benefits in randomized controlled trials of adults with self-perceived or clinical cognitive dysfunction. To date, adults with metabolic syndrome (MetS) but without cognitive dysfunction are understudied.

We have optimized the codons in an immunoglobulin kappa chain gene to those preferred in the yeast Saccharomyces cerevisiae. The mutant and wild type kappa chain genes were each fused with a synthetic invertase signal peptide that also contained only yeast–preferred codons, and expressed in the F762 yeast strain. The use of yeast–preferred codons resulted in a more than 5–fold increase in the rate of synthesis and at least a 50–fold increase in the steady state level of protein.

The human erythrocyte β-spectrin gene DNA has been cloned from overlapping human genomic phage and cosmid recombinants. The entire erythroid β-spectrin mRNA is encoded by 32 exons that range in size from 49 to 871 bases. The exon/intron junctions have been identified and the exons mapped. There is no correlation between intron positions and the repeat units of 106 amino acids within domain II of the β-spectrin gene. The scatter of the introns over the 17 repeats argues against the 106-amino-acid unit representing a minigene that underwent repeated duplication resulting in the present β-spectrin gene. In fact, the two largest exons, exon 14 (871 bp) and 16 (757 bp), extend over 4 and 3 repeat units of 106 amino acids, respectively, while repeat β10 is encoded by 4 exons. No single position of an intron in the β-spectrin gene is conserved between any of the 17 β-spectrin and 22 α-spectrin repeat units. The nucleotide sequences of the exon/intron boundaries conform to the consensus splice site sequences except for exon 20, whose 5′ donor splice-site sequence begins with GC. The β-spectrin isoform present in the human brain, the skeletal muscle, and the cardiac muscle is an alternatively spliced product of the erythroid β-spectrin gene. This splice site is located within the coding sequences of exon 32 and its utilization in nonerythroid tissues leads to the use of 4 additional downstream exons with a size range of 44 to 530 bp.

Rabies virus, a rhabdovirus, has a single (non-segmented) negative-strand RNA genome which is transcribed on infection to produce five polyadenylated complementary monocistronic mRNA species. Each of the virus-specific mRNAs representing a structural gene of the rabies virus genome1codes for a virion structural protein which corresponds in size to the apparent coding capacity of its mRNA2,3. The glycoprotein gene codes for a membrane-associated molecule which forms spike-like projections on the surface of mature rabies virions and is responsible for the induction and binding of virus-neutralizing antibodies to the virus4–6. To define the antigenic and immunogenic properties of rabies virus glycoprotein, we have cloned a cDNA copy of its mRNA sequence into pBR322 (ref. 7). Here we describe the characterization of the cDNA sequence, which has allowed us to predict several features of the glycoprotein from the deduced amino acid sequence.

Summary A cDNA clone in pBR322 that cross-hybridizes with a mouse carbonic anhydrase form II (CAII) probe has been sequenced and identified as mouse carbonic anhydrase form I (CAI). The 1224-base-pair clone encodes the entire 260-amino-acid protein and appears to contain an Alu-like element in the 3′ untranslated region. The deduced amino acid sequence exhibits 77% homology to human CAI and contains 17 of the 20 residues that are considered unique to and invariant for all mammalian CAI isozymes. The results of a detailed comparison of the nucleic acid sequences spanning the coding regions of mouse CAI and rabbit CAI have been used to calibrate an evolutionary clock for the carbonic anhydrases (CAs). These data have been applied to a comparison of the mouse CAI and CAII nucleic acid sequences to calculate the divergence time between the two genes. The divergence-time calculation provides the first estimation of the evolutionary relationship between CAs based entirely on nucleotide sequence comparison.

A rabbit monospecific antibody for mouse β-spectrin was used to screen a mouse anemic spleen cDNA expression library. A mouse β-spectrin cDNA clone was isolated and identified by its ability to make mouse β-spectrin-like antigens in Escherichia coli.This clone was used to probe total RNA from various mouse tissues. Anemic spleen RNA showed two strongly hybridizing RNA species of approximately 6 and 8 kb. Two very faintly hybridizing bands of about 6 kb and 10 kb could also be seen in total mouse brain RNA. All of these bands could be detected after hybridization under both stringent and nonstringent conditions. This suggests that erythroid β-spectrin may also be expressed in the brain. No bands could be detected in kidney, liver, or spleen RNA. Southern blot analysis of mouse genomic DNA showed a single hybridizing band after digestion with several restriction endonucleases even under nonstringent conditions. Nucleotide sequencing of the cDNA insert revealed almost complete identity between the N-terminus of the deduced amino acid sequence of the cDNA clone and the C-terminal 15 amino acids of a peptide derived from the β-8 repeat unit of human erythrocyte β-spectrin. The deduced amino acid sequence contained most of the conserved amino acids characteristic of the 106 amino acid repeat unit first found in human α-spectrin and thus provides the first evidence for a complete 106 amino acid repeat unit structure in β-spectrin.

Dimethyl sulfoxide-induced Friend cells were labeled for periods of 5-60 min. The denatured RNA was fractionated by sucrose gradient centrifugation and the distribution of α- and β-globin-specific [3H]RNA was determined by hybridization to hybrid plasmids containing mouse α- and β-globin DNA, respectively. After 5 min of labeling, a 15S peak of β-globin-specific (but not α-globin-specific) [3H]RNA was detected, next to an equal amount of 10S β-globin [3H]RNA. With increasing periods of labeling, the amount of 15S β-globin [3H]RNA remained constant but the amount 10S β-globin [3H]RNA increased steadily. α-Globin-specific [3H]RNA sedimented at 11 S after 5 min of labeling and at 9.5 S after longer labeling periods. Analysis of 15S globin-specific [3H]RNA purified by the poly(dC)-cDNA method [Curtis, P. J. & Weissmann, C. (1976) J. Mol. Biol.106, 1061-1075] showed oligonucleotides characteristic of β-globin mRNA but not of α-globin mRNA, as well as about 20 new oligonucleotides. Our results suggest that 10S β-globin mRNA arises via a 15S precursor that has a half-life of 5 min or less; 9.5S α-globin mRNA may be derived from an 11S precursor.

The enzyme 5-aminolevulinate synthase (ALA-S) catalyzes the first step in heme biosynthesis. In this study, the mouse erythroid gene has been cloned and analyzed in order to investigate the regulation of ALA-S expression during erythroid differentiation. The gene spans {small tilde}24 kbp and consists of 11 exons and 10 introns. The first exon is 37 bp, non-coding, and followed by a 6 kb intron. The mRNA capsite was mapped by primer extension and defines a promoter that contains no apparent TATA element. S1 nuclease analysis detects the presence at low levels of a 45 bp-deleted form of the ALA-S mRNA created by the use of an alternative splice site at the intron 2/exon 3 junction. Five DNAse I hypersensitive sites were detected in chromatin from uninduced and induced MEL cells. One site is at the promoter; the others are in the body of the gene. No significant differences were observed in the patterns or intensity of the hypersensitive sites in the uninduced and induced MEL cells, however, no sites in ALA-S were observed in NIH 3T3 cells or in deproteinized DNA. Thus, these sites are specific for erythroid chromatin but appear to be established at an earlier stage of differentiation than represented by the uninduced MEL cell.