BmCAP, a silkmoth gene encoding multiple protein isoforms characterized by SoHo and SH3 domains: expression analysis during ovarian follicular development.
CAP/ArgBP2/vinexin family proteins, adaptor proteins characterized by three SH3 domains at their C-termini and a SoHo domain towards their N-termini, are known to regulate cell adhesion, cytoskeletal organization, and growth factor signaling. Here we present the isolation and ovarian expression of the BmCAP gene which encodes CAP/ArgBP2/vinexin family proteins in the silkmoth, Bombyx mori. Screening for full-length cDNA clones identified three mRNA isoforms, BmCAP-A1, BmCAP-A2 and BmCAP-B, which show expression throughout ovarian follicular development. Using an antibody raised against a unique region between the SoHo and SH3 domains, BmCAP-A protein isoforms were identified that show specific expression in different compartments of the ovarian follicles. Immunofluorescence staining of the cells of the follicular epithelium establishes a dynamic pattern of BmCAP-A protein localization during choriogenesis. During early choriogenesis, BmCAP-A has a diffuse localization in the cytoplasm but could also be found concentrated at the apical and basal sides at the cell-cell junctions. During late choriogenesis, the diffuse cytoplasmic staining of BmCAP-A disappears while the staining pattern at the apical side resembles a blueprint for the eggshell surface structure. We suggest that BmCAP-A isoforms have important functions during ovarian development, which involve not only the traditional roles in actin organization or cell-cell adhesion but also the regulation of secretion of chorion proteins and the sculpting of the chorion surface.
Georgomanolis
Theodoros
T
Insect Molecular Genetics and Biotechnology, Institute of Biology, National Centre for Scientific Research Demokritos, Aghia Paraskevi Attikis, Athens, Greece.
Iatrou
Kostas
K
Swevers
Luc
L
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D012831:Bombyx / Q000235:genetics*; D002460:Cell Line; D003001:Cloning, Molecular; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D019476:Insect Proteins / Q000235:genetics* / Q000502:physiology*; D008969:Molecular Sequence Data; D010053:Ovary / Q000254:growth & development; D020033:Protein Isoforms; D018909:src Homology Domains / Q000235:genetics*
D019476:Insect Proteins; D020033:Protein Isoforms