title: Genome-wide identification, characterization of sugar transporter genes in the silkworm Bombyx mori and role in Bombyx mori nucleopolyhedrovirus (BmNPV) infection.
abstract: Sugar transporters play an essential role in controlling carbohydrate transport and are responsible for mediating the movement of sugars into cells. These genes exist as large multigene families within the insect genome. In insects, sugar transporters not only have a role in sugar transport, but may also act as receptors for virus entry. Genome-wide annotation of silkworm Bombyx mori (B. mori) revealed 100 putative sugar transporter (BmST) genes exists as a large multigene family and were classified into 11 sub families, through phylogenetic analysis. Chromosomes 27, 26 and 20 were found to possess the highest number of BmST paralogous genes, harboring 22, 7 and 6 genes, respectively. These genes occurred in clusters exhibiting the phenomenon of tandem gene duplication. The ovary, silk gland, hemocytes, midgut and malphigian tubules were the different tissues/cells enriched with BmST gene expression. The BmST gene BGIBMGA001498 had maximum EST transcripts of 134 and expressed exclusively in the malphigian tubule. The expression of EST transcripts of the BmST clustered genes on chromosome 27 was distributed in various tissues like testis, ovary, silk gland, malphigian tubule, maxillary galea, prothoracic gland, epidermis, fat body and midgut. Three sugar transporter genes (BmST) were constitutively expressed in the susceptible race and were down regulated upon BmNPV infection at 12h post infection (hpi). The expression pattern of these three genes was validated through real-time PCR in the midgut tissues at different time intervals from 0 to 30hpi. In the susceptible B. mori race, expression of sugar transporter genes was constitutively expressed making the host succumb to viral infection.
authors.affiliation: Genomics Division, Seribiotech Research Laboratory, Carmelaram Post, Kodathi, Bangalore 560 035, India.
authors.forename: Lekha
authors.initials: L
authors.lastname: Govindaraj
authors.affiliation: Genomics Division, Seribiotech Research Laboratory, Carmelaram Post, Kodathi, Bangalore 560 035, India.
authors.forename: Tania
authors.initials: T
authors.lastname: Gupta
authors.affiliation: Genomics Division, Seribiotech Research Laboratory, Carmelaram Post, Kodathi, Bangalore 560 035, India.
authors.forename: Vijaya Gowri
authors.initials: VG
authors.lastname: Esvaran
authors.affiliation: Genomics Division, Seribiotech Research Laboratory, Carmelaram Post, Kodathi, Bangalore 560 035, India.
authors.forename: Arvind Kumar
authors.initials: AK
authors.lastname: Awasthi
authors.affiliation: Genomics Division, Seribiotech Research Laboratory, Carmelaram Post, Kodathi, Bangalore 560 035, India. Electronic address: kmpvel@yahoo.com.
authors.forename: Kangayam M
authors.initials: KM
authors.lastname: Ponnuvel
mesh_terms: D000818:Animals; D012831:Bombyx / Q000235:genetics* / Q000821:virology; D002241:Carbohydrates / Q000235:genetics; D002875:Chromosomes / Q000235:genetics; D005786:Gene Expression Regulation; D049750:Genome, Insect; D007814:Larva; D009004:Monosaccharide Transport Proteins / Q000096:biosynthesis* / Q000235:genetics; D017924:Nucleopolyhedroviruses / Q000235:genetics* / Q000472:pathogenicity; D010802:Phylogeny
chemical_list: D002241:Carbohydrates; D009004:Monosaccharide Transport Proteins
keywords: BmNPV entry; Bombyx mori; Microarray; Sugar transporter; Susceptible race