Gene and protein expression in the epididymis of infertile c-ros receptor tyrosine kinase-deficient mice.
Transgenic male mice bearing inactive mutations of the receptor tyrosine kinase c-ros lack the initial segment of the epididymis and are infertile. Several techniques were applied to determine differences in gene expression in the epididymal caput of heterozygous fertile (HET) and infertile homozygous knockout (KO) males that may explain the infertility. Complementary DNA arrays, gene chips, Northern and Western blots, and immunohistochemistry indicated that some proteins were downregulated, including the initial segment/proximal caput-specific genes c-ros, cystatin-related epididymal-spermatogenic (CRES), and lipocalin mouse epididymal protein 17 (MEP17), whereas other caput-enriched genes (glutathione peroxidase 5, a disintegrin and metalloproteinase [ADAM7], bone morphogenetic proteins 7 and 8a, A-raf, CCAAT/enhancer binding protein beta, PEA3) were unchanged. Genes normally absent from the initial segment (gamma-glutamyltranspeptidase, prostaglandin D2 synthetase, alkaline phosphatase) were expressed in the undifferentiated proximal caput of the KO. More distally, lipocalin 2 (24p3), CRISP1 (formerly MEP7), PEBP (MEP9), and mE-RABP (MEP10) were unchanged in expression. Immunohistochemistry and Western blots confirmed the absence of CRES in epididymal tissue and fluid and the continued presence of CRES in spermatozoa of the KO mouse. The glutamate transporters EAAC1 (EAAT3) and EAAT5 were downregulated and upregulated, respectively. The genes of over 70 transporters, channels, and pores were detected in the caput epididymidis, but in the KO, only three were downregulated and six upregulated. The changes in these genes could affect sperm function by modifying the composition of epididymal fluid and explain the infertility of the KO males. These genes may be targets for a posttesticular contraceptive.
Cooper
Trevor G
TG
Institute of Reproductive Medicine of the University, D-48129 Münster, Germany. cooper@uni-muenster.de
Wagenfeld
Andrea
A
Cornwall
Gail A
GA
Hsia
Nelson
N
Chu
Sin Tak
ST
Orgebin-Crist
Marie-Claire
MC
Drevet
Joel
J
Vernet
Patrick
P
Avram
Cosmina
C
Nieschlag
Eberhard
E
Yeung
Ching-Hei
CH
D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D018076:DNA, Complementary / Q000096:biosynthesis / Q000235:genetics; D004822:Epididymis / Q000378:metabolism*; D015870:Gene Expression; D005838:Genotype; D007150:Immunohistochemistry; D007246:Infertility / Q000235:genetics* / Q000378:metabolism*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D020411:Oligonucleotide Array Sequence Analysis; D014176:Protein Biosynthesis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*
D018076:DNA, Complementary; D011518:Proto-Oncogene Proteins; D020794:Receptor Protein-Tyrosine Kinases; C483813:Ros1 protein, mouse