GEPHE SUMMARY Print
Gephebase Gene
Entry Status
Published
GepheID
GP00001905
Main curator
Courtier
PHENOTYPIC CHANGE
Trait Category
Trait State in Taxon A
Bombyx mori - wild-type
Trait State in Taxon B
Bombyx mori - Yellow cocoon (C) mutant - white cocoons - defect in the cellular uptake of lutein - silk gland selectively transporting beta-carotene
Ancestral State
Taxon A
Taxonomic Status
Taxon A
Latin Name
Common Name
domestic silkworm
Synonyms
domestic silkworm; silk moth; silkworm; Bombyx mori Linnaeus, 1758
Rank
species
Lineage
Show more ... xapoda; Insecta; Dicondylia; Pterygota; Neoptera; Holometabola; Amphiesmenoptera; Lepidoptera; Glossata; Neolepidoptera; Heteroneura; Ditrysia; Obtectomera; Bombycoidea; Bombycidae; Bombycinae; Bombyx
NCBI Taxonomy ID
is Taxon A an Infraspecies?
No
Taxon B
Latin Name
Common Name
domestic silkworm
Synonyms
domestic silkworm; silk moth; silkworm; Bombyx mori Linnaeus, 1758
Rank
species
Lineage
Show more ... xapoda; Insecta; Dicondylia; Pterygota; Neoptera; Holometabola; Amphiesmenoptera; Lepidoptera; Glossata; Neolepidoptera; Heteroneura; Ditrysia; Obtectomera; Bombycoidea; Bombycidae; Bombycinae; Bombyx
NCBI Taxonomy ID
is Taxon B an Infraspecies?
No
GENOTYPIC CHANGE
Generic Gene Name
Cameo2
Synonyms
Cameo2; BmSCRB4
String
-
Sequence Similarities
Belongs to the CD36 family.
GO - Molecular Function
-
GO - Biological Process
-
UniProtKB
Bombyx mori
GenebankID or UniProtKB
Presumptive Null
No
Molecular Type
Aberration Type
Molecular Details of the Mutation
difference in expression levels - three non synonymous mutations are also observed in the coding region - the gene is also named Cameo2
Experimental Evidence
Authors
Sakudoh T; Iizuka T; Narukawa J; Sezutsu H; Kobayashi I; Kuwazaki S; Banno Y; Kitamura A; et al. ... show more
Abstract
The transport pathway of specific dietary carotenoids from the midgut lumen to the silk gland in the silkworm, Bombyx mori, is a model system for selective carotenoid transport because several genetic mutants with defects in parts of this pathway have been identified that manifest altered cocoon pigmentation. In the wild-type silkworm, which has both genes, Yellow blood (Y) and Yellow cocoon (C), lutein is transferred selectively from the hemolymph lipoprotein to the silk gland cells where it is accumulated into the cocoon. The Y gene encodes an intracellular carotenoid-binding protein (CBP) containing a lipid-binding domain known as the steroidogenic acute regulatory protein-related lipid transfer domain. Positional cloning and transgenic rescue experiments revealed that the C gene encodes Cameo2, a transmembrane protein gene belonging to the CD36 family genes, some of which, such as the mammalian SR-BI and the fruit fly ninaD, are reported as lipoprotein receptors or implicated in carotenoid transport for visual system. In C mutant larvae, Cameo2 expression was strongly repressed in the silk gland in a specific manner, resulting in colorless silk glands and white cocoons. The developmental profile of Cameo2 expression, CBP expression, and lutein pigmentation in the silk gland of the yellow cocoon strain were correlated. We hypothesize that selective delivery of lutein to specific tissue requires the combination of two components: 1) CBP as a carotenoid transporter in cytosol and 2) Cameo2 as a transmembrane receptor on the surface of the cells.
Additional References
EXTERNAL LINKS
COMMENTS
Cameo2 is the silkworm ortholog of vertebrate SCARB1
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