Disease relevance of fem-1

• Mutations in fem-3 resemble alleles of fem-1 (previously characterized): putative null alleles result in complete feminization of XX and XO animals, transforming them into fertile females [1].

High impact information on fem-1

• Clones carrying a 5.5 kb fragment are able to rescue the progeny of a fem-1 mutant when injected into its oocytes [2].
• The product of fem-1, a nematode sex-determining gene, contains a motif found in cell cycle control proteins and receptors for cell-cell interactions [2].
• The major fem-1 transcript in both sexes is 2.4 kb and comprises 11 exons [2].
• Male sexual development in the nematode Caenorhabditis elegans requires the genes fem-1, fem-2, and fem-3 [3].
• To this extent, Fem1c(R3/R3) mice show no adverse effects in their sexual development or fertility or in the attenuation of neuronal cell death, another function that has been attributed to both fem-1 and a second mouse homolog, Fem1b [4].

Biological context of fem-1

• The minimal noncoding sequences required for activity of fem-1 transgenes suffice to direct expression of a fem-1::lacZ reporter gene in all somatic tissues in both sexes [5].
• Activity also requires any two or more introns, suggesting that splicing may enhance fem-1 expression [5].
• At least two genes, fem-1 and fem-2, control the initiation of spermatogenesis in XX (hermaphrodite) worms, and the entire spectrum of male differentiation in XO animals [6].
• Amino acid sequence analysis indicates that F1Aalpha has extensive homology to the sex-determining protein FEM-1 of the Caenorhabditis elegans, which is required for the development of all aspects of the male phenotype [7].

Other interactions of fem-1

• A double mutant harboring ts alleles of both fem-1 (formerly named isx-1; G. A. Nelson, K. K. Lew, and S. Ward, 1978, Dev. Biol. 66, 386-409) and fem-2 causes transformation of XO animals (normally male) into spermless hermaphrodites at restrictive temperature [8].

References