International Mammalian Genome Society

17th International Mouse Genome Conference

9-12 November 2003, Braunschweig, Germany

Plenary Presentations * Oral Presentations *
Poster Presentations: Behavioural Genetics and Genomics * Development and Stem Cells * Functional Genome Analysis * Mouse Models of Human Disease * Mouse System Biology Bioinformatics * Multigenic and Multifactorial Trait Analysis * Nutrition and Metabolic Disease * Phenotyping Methods Imaging * The Genetics and Genomics of Infectious Disease *
Verne Chapman Memorial Lecture * Table of Contents * Sponsor/Exhibitor List * Awards * Photographs

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ORAL PRESENTATION

TUESDAY 11 NOVEMBER
12:45 – 13:00 HRS

TARGETED DELETION OF FENS1 IN MICE LEADS TO INABILITY OF SPERM TO FERTILIZE

Bishop C
Baylor College of Medicine

Co-Authors: Rohozinski j, Ty M, Matzuk M, El Din N, Lamb D
Institutions: Baylor College of Medicine

Using meiotic mapping, we have placed the mouse homologue of the gene coding for the human FENS1 protein (FYVE domain containing protein localised to endosomes) within the 1.5Mb Jsd (juvenile spermatogonial depletion) critical interval on mouse chromosome 1. In situ RNA hybridization to mouse testes sections showed that Fens1 expression was restricted to the germline, being strongest during stage IV of spermatogenesis suggesting a possible role in germ cell development and fertility. Analysis of Fens1 function by gene targeting indicated that Fens1-/+ and Fens1-/- females were fully fertile as were heterozygous Fens1-/+ males. In contrast, Fens1-/- males were totally sterile. Complementation assays involving Fens1-/+ and jsd/+ compound male hereozygotes showed that Fens1 was not allelic to jsd excluding this gene as a candidate for the jsd mutation. Evaluation of Fens1-/- testes showed that they were of normal size with normal numbers of motile sperm in the epididymus. Histologically, the tubules were abnormal in that greater than 90% contained fully mature sperm. They also contained approximately 50% more Sertoli cells compared to normal Fens1+/+ or Fens1-/+ littermates, as reaveled by immunohistochemistry with a SOX9 antibody. In vivo and in vitro data reveal that sperm from Fens1-/- males are incapable of fertilizing normal oocytes. The putative FENS1 protein, which contains a FYVE domain and seven WD40 domains, is most probably involved in the regulation of endosomal function. We are currently investigating how impairement of this function affects the ability of Fens1-/- sperm to fertilize.