The amino acid sequence of a major human epididymis-specific protein was deduced from the nucleotide sequence of its cloned cDNA. The encoded product showed characteristics of a secretory protein, with a signal peptide followed by a small (approximately 10-kDa), acidic (pI 4.3), and cysteine-rich polypeptide. The positions of half-cysteines suggested that it was a two-domain member of the family of 'four-disulfide core' proteins to which a number of proteinase inhibitors belong. Southern blot analyses of human genomic DNA showed that the transcripts originated from a single copy gene. Northern blot and in situ transcript hybridization specifically localized the HE4 (human epididymis gene product) mRNA to the epithelial cells of the epididymal duct, predominantly within the distal sections. A possible function in sperm maturation as indicated by amino acid similarities to extracellular proteinase inhibitors of genital tract mucous secretions is discussed in the context of its tissue-specific transcription.
Stops, prevents or reduces the activity of serine-type endopeptidases, enzymes that catalyze the hydrolysis of nonterminal peptide bonds in a polypeptide chain; a serine residue (and a histidine residue) are at the active center of the enzyme.
The amino acid sequence of a major human epididymis-specific protein was deduced from the nucleotide sequence of its cloned cDNA. The encoded product showed characteristics of a secretory protein, with a signal peptide followed by a small (approximately 10-kDa), acidic (pI 4.3), and cysteine-rich polypeptide. The positions of half-cysteines suggested that it was a two-domain member of the family of 'four-disulfide core' proteins to which a number of proteinase inhibitors belong. Southern blot analyses of human genomic DNA showed that the transcripts originated from a single copy gene. Northern blot and in situ transcript hybridization specifically localized the HE4 (human epididymis gene product) mRNA to the epithelial cells of the epididymal duct, predominantly within the distal sections. A possible function in sperm maturation as indicated by amino acid similarities to extracellular proteinase inhibitors of genital tract mucous secretions is discussed in the context of its tissue-specific transcription.
The amino acid sequence of a major human epididymis-specific protein was deduced from the nucleotide sequence of its cloned cDNA. The encoded product showed characteristics of a secretory protein, with a signal peptide followed by a small (approximately 10-kDa), acidic (pI 4.3), and cysteine-rich polypeptide. The positions of half-cysteines suggested that it was a two-domain member of the family of 'four-disulfide core' proteins to which a number of proteinase inhibitors belong. Southern blot analyses of human genomic DNA showed that the transcripts originated from a single copy gene. Northern blot and in situ transcript hybridization specifically localized the HE4 (human epididymis gene product) mRNA to the epithelial cells of the epididymal duct, predominantly within the distal sections. A possible function in sperm maturation as indicated by amino acid similarities to extracellular proteinase inhibitors of genital tract mucous secretions is discussed in the context of its tissue-specific transcription.
The amino acid sequence of a major human epididymis-specific protein was deduced from the nucleotide sequence of its cloned cDNA. The encoded product showed characteristics of a secretory protein, with a signal peptide followed by a small (approximately 10-kDa), acidic (pI 4.3), and cysteine-rich polypeptide. The positions of half-cysteines suggested that it was a two-domain member of the family of 'four-disulfide core' proteins to which a number of proteinase inhibitors belong. Southern blot analyses of human genomic DNA showed that the transcripts originated from a single copy gene. Northern blot and in situ transcript hybridization specifically localized the HE4 (human epididymis gene product) mRNA to the epithelial cells of the epididymal duct, predominantly within the distal sections. A possible function in sperm maturation as indicated by amino acid similarities to extracellular proteinase inhibitors of genital tract mucous secretions is discussed in the context of its tissue-specific transcription.
Protein which inhibits serine proteases, a group of proteolytic enzymes which are characterized by a catalytically active serine residue in their active site.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.