title: Female qualities in males: vitellogenin synthesis induced by ovary transplants into the male silkworm, Bombyx mori.
abstract: Female qualities in males are common in vertebrates but have not been extensively reported in insects. Vitellogenin (Vg) is highly expressed in the female fat body and is generally required for the formation of yolk proteins in the insect egg. Vg upregulation is generally regarded as a female quality in female oviparous animals. In this study, we found that Bombyx mori Vg (BmVg) is especially highly expressed in the female pupa. Downregulation of the BmVg gene in the female pupa by RNA interference (RNAi) interfered with egg formation and embryonic development, showing the importance of BmVg in these processes. So, we used BmVg as a biomarker for female qualities in the silkworm. Hematoxylin-eosin staining and immunofluorescence histochemistry showed that ovary transplants induced BmVg synthesis in the male pupa fat body. Ovaries transplanted into male silkworms produced only a few eggs with deformed yolk granules. These results suggested that the amount of BmVg in the male silkworm was insufficient for eggs to undergo complete embryonic development. After 17-beta-estradiol was used to treat male pupae and male pupal fat bodies, BmVg was upregulated in vivo and in vitro. These findings indicated that the male silkworm has innate female qualities that were induced by a transplanted ovary and 17β-estradiol. However, in silkworms, female qualities in males are not as complete as in females.
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Congwen
authors.initials: C
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Guanwang
authors.initials: G
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Enxiang
authors.initials: E
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
authors.forename: Runmiao
authors.initials: R
authors.lastname: Xing
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China. Electronic address: xiaqy@swu.edu.cn.
authors.forename: Qingyou
authors.initials: Q
authors.lastname: Xia
mesh_terms: D000818:Animals; D012831:Bombyx / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D047108:Embryonic Development; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D017344:Genes, Insect; D008297:Male; D009866:Oogenesis; D010053:Ovary / Q000378:metabolism / Q000637:transplantation; D011679:Pupa / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D034622:RNA Interference; D012727:Sex Characteristics; D014819:Vitellogenins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D014819:Vitellogenins; D004958:Estradiol
keywords: 17-Beta estradiol; Egg formation; Female qualities; Male silkworm; Vitellogenin