Activation of the Complementary sex determiner (Csd) protein by amino acid polymorphism

• Applicant: Professor Dr. Martin Beye
• Subject Area: Evolutionary Cell and Developmental Biology (Zoology)
• Term: from 2009 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 108461341

• Final Report Year: 2023

Final Report Abstract

Sex in honeybees, Apis mellifera, is genetically determined by heterozygous versus homo/hemizygous genotypes involving numerous alleles at the single complementary sex determination locus. The molecular mechanism of sex determination is however unknown because there are more than 4950 known possible allele combinations, but only two sexes in the species. Here, we report how protein variants expressed from complementary sex determiner (csd) gene determine sex. In females, the amino acid differences between Csd variants at the potential specifying domain (PSD) directs the selection of a conserved coiled coil (CC) domain for binding and protein complexation. This recognition mechanism activates Csd proteins and thus the female pathway. In males, the absence of polymorphisms establishes other binding elements at PSD for binding and complexation of identical Csd proteins. This second recognition mechanism inactivates Csd proteins and commits male development via default pathway. Our results demonstrate that the recognition of different versus identical variants of a single protein is a mechanism to determine sex.

Publications

• Improving genetic transformation rates in honeybees. Scientific Reports, 8(1).
  Otte, M.; Netschitailo, O.; Kaftanoglu, O.; Wang, Y.; Page, R. E. & Beye, M.
  
• A genetic switch for worker nutrition-mediated traits in honeybees. PLOS Biology, 17(3),e3000171.
  Roth, Annika; Vleurinck, Christina; Netschitailo, Oksana; Bauer, Vivien; Otte, Marianne; Kaftanoglu, Osman; Page, Robert E. & Beye, Martin
  
• Sexual diversification of splicing regulation during embryonic development in honeybees (Apis mellifera), A haplodiploid system. Insect Molecular Biology, 31(2), 170-176.
  Netschitailo, Oksana; Raub, Stephan; Kaftanoglu, Osman & Beye, Martin
  
• Recognition of polymorphic Csd proteins determines sex in the honeybee. Science Advances, 9(40).
  Otte, Marianne; Netschitailo, Oksana; Weidtkamp-Peters, Stefanie; Seidel, Claus A. M. & Beye, Martin
  
• The function and evolution of a genetic switch controlling sexually dimorphic eye differentiation in honeybees. Nature Communications, 14(1).
  Netschitailo, Oksana; Wang, Yidong; Wagner, Anna; Sommer, Vivien; Verhulst, Eveline C. & Beye, Martin