Molecular characterization of radiation- and chemically induced mutations associated with neuromuscular tremors, runting, juvenile lethality, and sperm defects in jdf2 mice

Abstract

The juvenile development and fertility-2 (jdf2) locus, also called runty-jerky-sterile (rjs), was originally identified through complementation studies of radiation-induced p-locus mutations. Studies with a series of ethylnitrosourea (ENU)-induced jdf2 alleles later indicated that the pleiotropic effects of these mutations were probably caused by disruption of a single gene. Recent work has demonstrated that the jdf2 phenotype is associated with deletions and point mutations in Herc2, a gene encoding an exceptionally large guanine nucleotide exchange factor protein thought to play a role in vesicular trafficking. Here we describe the molecular characterization of a collection of radiation- and chemically induced jdf2/Herc2 alleles. Ten of the 13 radiation-induced jdf2 alleles we studied are deletions that remove specific portions of the Herc2 coding sequence; DNA rearrangements were also detected in two additional mutations. Our studies also revealed that Herc2 transcripts are rearranged, not expressed, or are present in significantly altered quantities in animals carrying most of the jdf2 mutations we analyzed, including six independent ENU-induced alleles. These data provide new molecular clues regarding the wide range of jdf2 and p phenotypes that are expressed by this collection of recently generated and classical p-region mutations.

Physical and Functional Interaction of the HECT Ubiquitin-protein Ligases E6AP and HERC2

“…Furthermore, we have so far not obtained any evidence that, through its interaction with HERC2, E6AP may be involved in DNA repair processes. In this context, it should be noted that spontaneous mutations in the murine Herc2 gene have been associated with the phenotypes of so-called rjs or jdf2 mice (33,34). Although not contradictory, the phenotypes of these mice are not obviously linked to deficiencies in DNA repair pathways supporting the notion that HERC2 is a multifunctional protein.…”

Mutation of l7Rn3 Shows That Odz4 Is Required for Mouse Gastrulation

“…and hemizygous deletion animals (Rinchik et al 1990 lished techniques (Lossie et al 1993). The absence of the M. musculus-specific fragment in DNA from Tyr c-deletion /ϩ SPT F 1 animals indicates that a probe is deleted and therefore local-MATERIALS AND METHODS ized within the l7Rn3 critical region.…”

Functional annotation of mammalian genomic DNA sequence by chemical mutagenesis: A fine-structure genetic mutation map of a 1- to 2-cM segment of mouse chromosome 7 corresponding to human chromosome 11p14-p15

“…The phenotyping protocols used in such strategies can range from simple to complex and can be narrowly or broadly focused, with the output of any experiment dependent largely on the discriminating power of the phenotyping used. The extensive homologies between the genomes of mouse and human make it feasible to use the mouse for discovery of new mutations and phenotypes that aid in the functional annotation of the corresponding human DNA sequence and transcription maps.The region of mouse chromosome (Chr) 7 surrounding the pink-eyed dilution (p) locus that shares homology with human genomic regions 15q11-q13 and 11p14-p15 is being characterized by both genetic and molecular approaches (15,(19)(20)(21)(22)(23)(24)(25)(26). We previously reported initial results of a hemizygosity-screen strategy for recovering ENU-induced recessive mutations within the 4-to 5-cM Del(ru2 p) 46DFiOD deletion (15); this strategy is similar to a mutation-recovery experiment carried out for a 6-to 11-cM deletion at the more distally mapping Chr 7 tyrosinase [Tyr; previously, albino (c)] locus (14,16).…”

“…The region of mouse chromosome (Chr) 7 surrounding the pink-eyed dilution (p) locus that shares homology with human genomic regions 15q11-q13 and 11p14-p15 is being characterized by both genetic and molecular approaches (15,(19)(20)(21)(22)(23)(24)(25)(26). We previously reported initial results of a hemizygosity-screen strategy for recovering ENU-induced recessive mutations within the 4-to 5-cM Del(ru2 p) 46DFiOD deletion (15); this strategy is similar to a mutation-recovery experiment carried out for a 6-to 11-cM deletion at the more distally mapping Chr 7 tyrosinase [Tyr; previously, albino (c)] locus (14,16).…”