title: Identification and function of Abdominal-A in the silkworm, Bombyx mori.
abstract: Abdominal-A (adb-A) is a key gene in the development of insects. To understand its function in the silkworm, we cloned 1193 bp of the abd-A gene of Bombyx mori (Bmabd-A), including the complete coding sequence and part of the 3' untranslated region sequence. Bmabd-A has at least three mRNA splice variants with coding sequences of lengths 1032, 1044 and 1059 bp, encoding 343, 347 and 352 amino acids, respectively. Each splice variant of Bmabd-A has three exons and differs only in second exon size. Bmabd-A was expressed at low levels in unfertilized eggs, but increased gradually in fertilized eggs after laying 22 h. Bmabd-A expression decreased in ant silkworms (newly hatched silkworms). After RNA interference for Bmabd-A, the embryos had two mutant phenotypes, either completely or partially absent abdominal feet from the third to sixth abdominal segments, suggesting that Bmabd-A is responsible for normal development of the third to sixth abdominal segments during embryonic development.
authors.affiliation: Southwest University, Chongqing, China.
authors.forename: M-H
authors.initials: MH
authors.lastname: Pan
authors.forename: X-Y
authors.initials: XY
authors.lastname: Wang
authors.forename: C-L
authors.initials: CL
authors.lastname: Chai
authors.forename: C-D
authors.initials: CD
authors.lastname: Zhang
authors.forename: C
authors.initials: C
authors.lastname: Lu
authors.forename: Z-H
authors.initials: ZH
authors.lastname: Xiang