Search
semenogelin-1; semenogelin I; SGI; contains: alpha-inhibin-92; alpha-inhibin-31; seminal basic protein (SEMG1, SEMG)
Function:
- predominant protein in semen.
- participates in formation of a gel matrix entrapping the accessory gland secretions & ejaculated spermatozoa
- fragments of semenogelin &/or fragments of related proteins may contribute to activation of progressive sperm movements as the gel-forming proteins are fragmented by KLK3/PSA
- alpha-inhibin-92 & alpha-inhibin-31, derived from the proteolytic degradation of semenogelin, inhibit secretion of pituitary FSH transglutaminase substrate
- rapidly cleaved after ejaculation by KLK3/PSA, resulting in liquefaction of the semen coagulum & the progressive release of motile spermatozoa
- occurs in disulfide-linked complexes which may also contain 2 less abundant 71-kD & 76-kD semenogelin-related polypeptides
Structure: belongs to the semenogelin family
Compartment: secreted
Alternative splicing: named isoforms=2
Expression: seminal vesicle
General
glycoprotein
protein precursor
secreted protein
Properties
SIZE: entity length = 462 aa
MW = 52 kD
COMPARTMENT: extracellular compartment
MOTIF: signal sequence {1-23}
consensus repeat {174-215}
consensus repeat {234-275}
MOTIF: cysteine residue {C239}
MODIFICATION: cysteine residue {C-INTERCHAIN}
consensus repeat {282-339}
consensus repeat {342-399}
consensus repeat {414-455}
PRECURSOR-FOR: seminal basic protein
COMPARTMENT: extracellular compartment
MOTIF: glycosylation site
ALPHA-INHIBIN-92
ALPHA-INHIBIN-31
Database Correlations
OMIM 182140
UniProt P04279
Pfam PF05474
Entrez Gene 6406
Kegg hsa:6406
References
- UniProt :accession P04279
- Protein Spotlight; Shackled sperm - Issue 62 of September 2005
http://web.expasy.org/spotlight/back_issues/sptlt062.shtml