title: Actin dynamics regulate subcellular localization of the F-actin-binding protein PALLD in mouse Sertoli cells.
abstract: Sertoli cells undergo terminal differentiation at puberty to support all phases of germ cell development, which occurs in the mouse beginning in the second week of life. By ∼18 days postpartum (dpp), nearly all Sertoli cells have ceased proliferation. This terminal differentiation is accompanied by the development of unique and regionally concentrated filamentous actin (F-actin) structures at the basal and apical aspects of the seminiferous epithelium, and this reorganization is likely to involve the action of actin-binding proteins. Palladin (PALLD) is a widely expressed F-actin-binding and bundling protein recently shown to regulate these structures, yet it is predominantly nuclear in Sertoli cells at puberty. We found that PALLD localized within nuclei of primary Sertoli cells grown in serum-free media but relocalized to the cytoplasm upon serum stimulation. We utilized this system with in vivo relevance to Sertoli cell development to investigate mechanisms regulating nuclear localization of this F-actin-binding protein. Our results indicate that PALLD can be shuttled from the nucleus to the cytoplasm, and that this relocalization occurred following depolymerization of the F-actin cytoskeleton in response to cAMP signaling. Nuclear localization was reduced in Hpg-mutant testes, suggesting the involvement of gonadotropin signaling. We found that PALLD nuclear localization was unaffected in testis tissues from LH receptor and androgen receptor-mutant mice. However, PALLD nuclear localization was reduced in the testes of FSH receptor-mutant mice, suggesting that FSH signaling during Sertoli cell maturation regulates this subcellular localization.
authors.affiliation: Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Niedenberger
authors.affiliation: Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
authors.forename: Vesna A
authors.initials: VA
authors.lastname: Chappell
authors.affiliation: Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
authors.forename: Carol A
authors.initials: CA
authors.lastname: Otey
authors.affiliation: Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA geyerc@ecu.edu.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Geyer
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism*; D000199:Actins / Q000378:metabolism*; D021581:Active Transport, Cell Nucleus; D000818:Animals; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000235:genetics / Q000378:metabolism; D006801:Humans; D028884:Karyopherins / Q000378:metabolism; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D010750:Phosphoproteins / Q000378:metabolism*; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D011962:Receptors, FSH / Q000235:genetics / Q000378:metabolism; D011974:Receptors, LH / Q000235:genetics / Q000378:metabolism; D012708:Sertoli Cells / Q000378:metabolism*; D020741:rho GTP-Binding Proteins / Q000378:metabolism; D000097606:Exportin 1 Protein
chemical_list: D000199:Actins; D000242:Cyclic AMP; D003598:Cytoskeletal Proteins; D005640:Follicle Stimulating Hormone; D007987:Gonadotropin-Releasing Hormone; D028884:Karyopherins; D007986:Luteinizing Hormone; D010750:Phosphoproteins; D011498:Protein Precursors; D011944:Receptors, Androgen; D018160:Receptors, Cytoplasmic and Nuclear; D011962:Receptors, FSH; D011974:Receptors, LH; D020741:rho GTP-Binding Proteins; D000097606:Exportin 1 Protein; C485873:palladin protein, mouse; C050866:progonadoliberin I