|
|
|
Research Papers
Laboratory of Molecular Biology, National Cancer Institute, Bethesda, Maryland 20892.
Abstract
Transgenic mice were generated with a human epidermal growth factor (EGF) receptor cDNA driven by the chicken beta-actin gene promoter. One line (AE24) that exhibited a unique expression pattern in which dramatically elevated levels of EGF receptor RNA were found only in the testis was established, suggesting that the beta-actin promoter was being influenced by an adjacent testis-specific enhancer. EGF receptor RNA was detected in primary spermatocytes, whereas the synthesis of receptor protein was restricted to elongate spermatids, indicating that transgene expression was under translational control. At spermiation, the EGF receptor was sequestered in residual bodies and excluded from mature sperm by a compartmentalization mechanism. About half of AE24 homozygous males were sterile because of sperm paralysis, whereas heterozygous males and females of either genotype were completely fertile. Electron microscopic analysis of sperm flagella from sterile AE24 homozygotes revealed an aberrant axonemal structure in which outer doublet microtubules were missing from the middle piece, resembling changes observed in the sperm of some infertile humans. Flagellar axonemal disassembly was observed in the vas deferens and epididymis but not in the testis, suggesting that outer doublets were assembled in a grossly normal manner but possessed a latent instability. These results demonstrate that in the AE24 mouse line the EGF receptor transgene was integrated into and inactivated an endogenous autosomal gene, causing sperm flagellar axonemal disruption and male sterility.
This article has been cited by other articles:
![]() |
P. R. Manna, I. T. Huhtaniemi, X.-J. Wang, D. W. Eubank, and D. M. Stocco Mechanisms of Epidermal Growth Factor Signaling: Regulation of Steroid Biosynthesis and the Steroidogenic Acute Regulatory Protein in Mouse Leydig Tumor Cells Biol Reprod, November 1, 2002; 67(5): 1393 - 1404. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Sampson, W. K. Decker, A. L. Beaudet, W. Ruitenbeek, D. Armstrong, M. J. Hicks, and W. J. Craigen Immotile Sperm and Infertility in Mice Lacking Mitochondrial Voltage-dependent Anion Channel Type 3 J. Biol. Chem., October 12, 2001; 276(42): 39206 - 39212. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. R. Haft, M. de la Luz Sierra, V. A. Barr, D. H. Haft, and S. I. Taylor Identification of a Family of Sorting Nexin Molecules and Characterization of Their Association with Receptors Mol. Cell. Biol., December 1, 1998; 18(12): 7278 - 7287. [Abstract] [Full Text] |
||||
![]() |
C Jhappan, D Gallahan, C Stahle, E Chu, G H Smith, G Merlino, and R Callahan Expression of an activated Notch-related int-3 transgene interferes with cell differentiation and induces neoplastic transformation in mammary and salivary glands. Genes & Dev., March 1, 1992; 6(3): 345 - 355. [Abstract] [PDF] |
||||
![]() |
S. A. Phillips, V. A. Barr, D. H. Haft, S. I. Taylor, and C. R. Haft Identification and Characterization of SNX15, a Novel Sorting Nexin Involved in Protein Trafficking J. Biol. Chem., February 9, 2001; 276(7): 5074 - 5084. [Abstract] [Full Text] [PDF] |
||||