| Strain Characteristics |
Their phenotype is caused by autosomal recessive mutation, <i>as</i> (aspermia). Homozygous mutant males show arrest of spermatogenesis, mainly at the pachytene stage (Ikadai, 1992). Testis weight of mutants was about one-third of that of normal males. A large basophilic inclusion-like body existed in the cytoplasm of late pachytene spermatocytes. The result of spermatogonial transplantation suggested that defective spermatogenesis is caused by defects of both germ cell itself and somatic cell component such as blood-testis barrier (Noguchi, 2002). Heterozygous males and homozygous females are fertile.
<i>as</i>was revealed to be caused by a genomic deletion including exon 8 of Fkbp6 gene on rat chromosome 12 (Crackower, 2003). (May 31, 2010) |
| References |
Ikadai H, Noguchi J, Yoshida M, Imamichi T.
An aspermia rat mutant (as/as) with spermatogenic failure at meiosis.
J Vet Med Sci. 1992 Aug;54(4):745-9.
Noguchi J, Toyama Y, Yuasa S, Kikuchi K, Kaneko H.
Hereditary defects in both germ cells and the blood-testis barrier system in as-mutant rats: evidence from spermatogonial transplantation and tracer-permeability analysis.
Biol Reprod. 2002 Sep;67(3):880-8.
Crackower MA, Kolas NK, Noguchi J, Sarao R, Kikuchi K, Kaneko H, Kobayashi E, Kawai Y, Kozieradzki I, Landers R, Mo R, Hui CC, Nieves E, Cohen PE, Osborne LR, Wada T, Kunieda T, Moens PB, Penninger JM.
Essential role of Fkbp6 in male fertility and homologous chromosome pairing in meiosis.
Science. 2003 May 23;300(5623):1291-5. |