IQ motif-containing G (Iqcg) is required for mouse spermiogenesis.

Spermiogenesis in mammals is the process by which the newly formed products of meiosis, haploid spermatids, undergo a dramatic morphological transformation from round cells into flagellated spermatozoa. The underlying genetic control of spermiogenesis is complicated and not well-characterized. We have used forward genetic screens in mice to illuminate the mechanisms of spermatozoon development.

High resolution mapping and positional cloning of ENU-induced mutations in the Rw region of mouse chromosome 5.

Background: Forward genetic screens in mice provide an unbiased means to identify genes and other functional genetic elements in the genome. Previously, a large scale ENU mutagenesis screen was conducted to query the functional content of a ~50 Mb region of the mouse genome on proximal Chr 5. The majority of phenotypic mutants recovered were embryonic lethals.

Different regulatory systems operate in the midpiece and principal piece of the mammalian sperm flagellum.

In mammalian sperm, the flagellar midpiece and principal piece contain different signalling molecules and ion channels. For example, the soluble adenylyl cyclase (sAC), which is required for activation of motility, is restricted to the midpiece, while the plasma membrane calcium channels CatSper1 and CatSper2, which are required for hyperactivation of motility, are restricted to the principal piece. The midpiece and principal piece are partially separated by a barrier called the annulus, yet despite this and the differential distribution of signalling molecules, they normally appear to work together to produce a wave that propagates smoothly down the tail.