RRC ID |
571
|
Author |
Sakudoh T, Tsuchida K, Kataoka H.
|
Title |
BmStart1, a novel carotenoid-binding protein isoform from Bombyx mori, is orthologous to MLN64, a mammalian cholesterol transporter.
|
Journal |
Biochem Biophys Res Commun
|
Abstract |
Carotenoid-binding protein (CBP) from the silkworm Bombyx mori is an essential molecule for carotenoid dependent cocoon pigmentation. We identified a novel isoform of CBP, Start1 of B. mori (BmStart1). BmStart1 contains a membrane-spanning MENTAL domain in its N-terminus and a lipid-binding START domain in its C-terminus. This domain architecture is identical to the mammalian MLN64 and Start1 of Drosophila melanogaster (DmStart1), both of which have been implicated to function in cholesterol transport and regulation of steroidogenesis. BmStart1 is expressed in both white and yellow cocoon strains of B. mori, while CBP is only detected in the yellow cocoon strain. BmStart1 mRNA abundance in the prothoracic gland, the main ecdysteroidogenic tissue, positively correlates with changes in the hemolymph ecdysteroid level. Genomic sequence analysis revealed that BmStart1 and CBP are generated from the same gene locus by alternative splicing. Splice site comparison and homology search indicate that BmStart1 is orthologous to both MLN64 and DmStart1. This study implies that alternative splicing of the BmStart1/CBP gene generates unique protein isoforms whose endogenous ligands, sterol or carotenoid, are structurally different.
|
Volume |
336(4)
|
Pages |
1125-35
|
Published |
2005-11-4
|
DOI |
10.1016/j.bbrc.2005.08.241
|
PII |
S0006-291X(05)01956-X
|
PMID |
16169523
|
MeSH |
Amino Acid Sequence
Animals
Base Sequence
Bombyx / genetics
Bombyx / metabolism*
Carotenoids / metabolism*
Carrier Proteins / genetics
Carrier Proteins / physiology*
Cholesterol / metabolism
Drosophila Proteins / genetics
Ecdysteroids / metabolism
Hemolymph / metabolism
Membrane Transport Proteins / genetics
Molecular Sequence Data
Protein Isoforms / genetics
Protein Isoforms / physiology
Protein Structure, Tertiary
Sequence Homology, Amino Acid
|
IF |
2.985
|
Times Cited |
19
|
WOS Category
|
BIOPHYSICS
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
Resource |
Silkworms |
EST database ? |