Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

CIB1 is essential for mouse spermatogenesis.

CIB1 is a 22-kDa calcium binding, regulatory protein with approximately 50% homology to calmodulin and calcineurin B. CIB1 is widely expressed and binds to a number of effectors, such as integrin alphaIIb, PAK1, and polo-like kinases, in different tissues. However, the in vivo functions of CIB1 are not well understood. To elucidate the function of CIB1 in whole animals, we used homologous recombination in embryonic stem cells to generate Cib1(-/-) mice. Although Cib1(-/-) mice grow normally, the males are sterile due to disruption of the haploid phase of spermatogenesis. This is associated with reduced testis size and numbers of germ cells in seminiferous tubules, increased germ cell apoptosis, and the loss of elongated spermatids and sperm. Cib1(-/-) testes also show increased mRNA and protein expression of the cell cycle regulator Cdc2/Cdk1. In addition, mouse embryonic fibroblasts (MEFs) derived from Cib1(-/-) mice exhibit a much slower growth rate compared to Cib1(+/+) MEFs, suggesting that CIB1 regulates the cell cycle, differentiation of spermatogenic germ cells, and/or differentiation of supporting Sertoli cells.

Pubmed ID: 16982698


  • Yuan W
  • Leisner TM
  • McFadden AW
  • Clark S
  • Hiller S
  • Maeda N
  • O'Brien DA
  • Parise LV


Molecular and cellular biology

Publication Data

November 1, 2006

Associated Grants

  • Agency: NHLBI NIH HHS, Id: 2-P01-HL06350
  • Agency: NHLBI NIH HHS, Id: 2-P01-HL45100
  • Agency: NHLBI NIH HHS, Id: F32 HL10381
  • Agency: NHLBI NIH HHS, Id: HL42630
  • Agency: NICHD NIH HHS, Id: U54 HD035041
  • Agency: NICHD NIH HHS, Id: U54-HD35041

Mesh Terms

  • Acetic Acid
  • Animals
  • Apoptosis
  • CDC2 Protein Kinase
  • Calcium-Binding Proteins
  • Cell Proliferation
  • Epididymis
  • Fibroblasts
  • Formaldehyde
  • Infertility, Male
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Picrates
  • Recombination, Genetic
  • Spermatids
  • Spermatocytes
  • Spermatogenesis
  • Testis