Molecular cloning and tissue-specific expression analysis of mouse spinesin, a type II transmembrane serine protease 5.
We have previously reported novel serine proteases isolated from cDNA libraries of the human and mouse central nervous system (CNS) by PCR using degenerate oligodeoxyribonucleotide primers designed on the basis of the serine protease motifs, AAHC and DSGGP. Here we report a newly isolated serine protease from the mouse CNS. This protease is homologous (77.9% identical) to human spinesin type II transmembrane serine protease 5. Mouse spinesin (m-spinesin) is also composed of (from the N-terminus) a short cytoplasmic domain, a transmembrane domain, a stem region containing a scavenger-receptor-like domain, and a serine protease domain, as is h-spinesin. We also isolated type 1, type 2, and type 3 variant cDNAs of m-spinesin. Full-length spinesin (type 4) and type 3 contain all the domains, whereas type 1 and type 2 variants lack the cytoplasmic, transmembrane, and scavenger-receptor-like domains. Subcellular localization of the variant forms was analyzed using enhanced green fluorescent protein (EGFP) fusion proteins. EGFP-type 4 fusion protein was predominantly localized to the ER, Golgi apparatus, and plasma membrane, whereas EGFP-type 1 was localized to the cytoplasm, reflecting differential classification of m-spinesin variants into transmembrane and cytoplasmic types. We analyzed the distribution of m-spinesin variants in mouse tissues, using RT-PCR with variant-specific primer sets. Interestingly, transmembrane-type spinesin, types 3 and 4, was specifically expressed in the spinal cord, whereas cytoplasmic type, type 1, was expressed in multiple tissues, including the cerebrum and cerebellum. Therefore, m-spinesin variants may have distinct biological functions arising from organ-specific variant expression.
Department of Cell Biology, Institute for Geriatrics, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
Yoshihisa
Y
Watanabe
Akira
A
Okui
Shinichi
S
Mitsui
Kentaro
K
Kawarabuki
Tatsuyuki
T
Yamaguchi
Hidetoshi
H
Uemura
Nozomi
N
Yamaguchi
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D051379:Mice; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D012697:Serine Endopeptidases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D014018:Tissue Distribution
D007527:Isoenzymes; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D011993:Recombinant Fusion Proteins; D012697:Serine Endopeptidases; C450831:TMPRSS5 protein, human; C494430:spinesin protein, mouse