Karakterisasi Gen Ser2 pada Ulat Sutera Domestik (Bombyx mori)

Abstract

Insect of the family Bombycidae is a beneficial insect because it produces cocoon as a source of natural silk fibers. Silk fibers from Bombyx mori is produced in the silk gland at the stage of last instar larvae before the formation of the cocoon. The main components of silk are fibroin and serisin. Ser2 gene dominates process of fiber formation when the caterpillar is on the growth stage. The study of genes characteristic serisin 2 in B. mori is still limited. The objective of this study was to analyze characteristic of Ser2 gene in silkworm B. mori originated from Candiroto. Middle silk gland (MSG) of the silkworm B. mori was extracted for the RNA analysis using the RNeasy Mini Kit (Qiagen). Complementary DNA (cDNA) was synthesized from RNA using Revertaid Transcriptase (Thermo Science Inc). It was then amplified using three pairs of the primers, i.e two pairs of housekeeping genes and one pair of Ser2 genes. The result of Ser2 gene amplification was sequenced to obtain composition of nucleotide bases. Sampels BC8 and BC10 were successfully sequenced and then aligned using Molecular Evolutionary Genetic Analysis software version 4 (MEGA 4.0). To obtain kindship percentage, those sequenced samples were compared with other individuals acquired from gene bank using Basic Local Alignment Search Tool-nucleotide ( BLAST n) program. The results was that B. mori BC8 and BC10 having similarity as high as 100% with Bombyx mori serisin 2 (Ser2) transcript variant 2, mRNA (Genebank: NM001172817.1), Bombyx mori serisin 2 (Ser2) transcript variant 1, mRNA (Genebank: NM001172816.1) dan Bombyx mori serisin 2 precursor (Ser2) gene, complete cds alternatively spliced (Genebank: GQ381286.1) .