Isolation of a new class of cysteine-glycine-proline-rich beta-proteins (beta-keratins) and their expression in snake epidermis.

Scales of snakes contain hard proteins (beta-keratins), now referred to as keratin-associated beta-proteins. In the present study we report the isolation, sequencing, and expression of a new group of these proteins from snake epidermis, designated cysteine-glycine-proline-rich proteins. One deduced protein from expressed mRNAs contains 128 amino acids (12.

Forty keratin-associated beta-proteins (beta-keratins) form the hard layers of scales, claws, and adhesive pads in the green anole lizard, Anolis carolinensis.

Using bioinformatic methods we have detected the genes of 40 keratin-associated beta-proteins (KAbetaPs) (beta-keratins) from the first available draft genome sequence of a reptile, the lizard Anolis carolinensis (Broad Institute, Boston). All genes are clustered in a single but not yet identified chromosomal locus, and contain a single intron of variable length. 5'-RACE and RT-PCR analyses using RNA from different epidermal regions show tissue-specific expression of different transcripts.

Transcriptional control of human steroid sulfatase.

Steroid sulfatase (STS) is a membrane-bound microsomal enzyme that hydrolyzes various alkyl and aryl steroid sulfates, leading to the in situ formation of biologically active hormones. The entire human STS gene spans over approximately 200kbp of which the first 100kbp include the regulatory region, while the STS-coding region is located downstream. Previous studies indicated that STS expression, in different human tissues, could be regulated by at least six different promoters associated with alternative first exons.

Evolution of hard proteins in the sauropsid integument in relation to the cornification of skin derivatives in amniotes.

Hard skin appendages in amniotes comprise scales, feathers and hairs. The cell organization of these appendages probably derived from the localization of specialized areas of dermal-epidermal interaction in the integument. The horny scales and the other derivatives were formed from large areas of dermal-epidermal interaction.

Transcriptional control of human organic anion transporting polypeptide 2B1 gene.

Organic anion transporting polypeptides (OATPs) are a group of transmembrane carriers with a wide spectrum of amphipathic substrates. In particular, OATP2B1 (previously called OATP-B) can transport steroid hormone conjugates and is expressed in organs with steroidogenic activity, such as placenta, brain and skin. In this work, we have analyzed the transcription of the OATP2B1 gene (SLCO2B1) in 14 different human tissues by means of 5'-RACE analysis.

Beta-keratins of turtle shell are glycine-proline-tyrosine rich proteins similar to those of crocodilians and birds.

This study presents, for the first time, sequences of five beta-keratin cDNAs from turtle epidermis obtained by means of 5'- and 3'-rapid amplification of cDNA ends (RACE) analyses. The deduced amino acid sequences correspond to distinct glycine-proline-serine-tyrosine rich proteins containing 122-174 amino acids. In situ hybridization shows that beta-keratin mRNAs are expressed in cells of the differentiating beta-layers of the shell scutes.

Identification of reptilian genes encoding hair keratin-like proteins suggests a new scenario for the evolutionary origin of hair.

The appearance of hair is one of the main evolutionary innovations in the amniote lineage leading to mammals. The main components of mammalian hair are cysteine-rich type I and type II keratins, also known as hard alpha-keratins or "hair keratins." To determine the evolutionary history of these important structural proteins, we compared the genomic loci of the human hair keratin genes with the homologous loci of the chicken and of the green anole lizard Anolis carolinenis.

Beta-keratins of the crocodilian epidermis: composition, structure, and phylogenetic relationships.

Nucleotide and deduced amino acid sequences of three beta-keratins of Nile crocodile scales are presented. Using 5'- and 3'-RACE analysis, two cDNA sequences of 1 kb (Cr-gptrp-1) and 1.5 kb (Cr-gptrp-2) were determined, corresponding to 17.

The expression of the human steroid sulfatase-encoding gene is driven by alternative first exons.

We have analyzed steroid sulfatase (STS) gene transcription in 10 human tissues: ovary, adrenal cortex, uterus, thyroid, liver, pancreas, colon, mammary gland, dermal papilla of the hair follicle, and peripheral mononuclear leukocytes. Overall, six different promoters were found to drive STS expression, giving rise to transcripts with unique first exons that were labeled 0a, 0b, 0c, 1a, 1c, and 1d, of which the last two and 0c are newly reported. All of them, except exon 1d, vary in length owing to the occurrence of multiple transcriptional start sites.

Beta-keratins of differentiating epidermis of snake comprise glycine-proline-serine-rich proteins with an avian-like gene organization.

Beta-keratins of reptilian scales have been recently cloned and characterized in some lizards. Here we report for the first time the sequence of some beta-keratins from the snake Elaphe guttata. Five different cDNAs were obtained using 5'- and 3'-RACE analyses.

RETRACTED: Occurrence of steroid-converting enzymes in the gonads of the Manila clam, Ruditapes philippinarum (Adams and Reeve, 1850), and correlation with the gametogenic cycle.

This article has been retracted consistent with Elsevier Policy on Article Withdrawal. Please see http://www.elsevier.

Cloning and characterization of scale beta-keratins in the differentiating epidermis of geckoes show they are glycine-proline-serine-rich proteins with a central motif homologous to avian beta-keratins.

The beta-keratins constitute the hard epidermis and adhesive setae of gecko lizards. Nucleotide and amino acid sequences of beta-keratins in epidermis of gecko lizards were cloned from mRNAs. Specific oligonucleotides were used to amplify by 3'- and 5'-rapid amplification of cDNA ends analyses five specific gecko beta-keratin cDNA sequences.