Mammalian germ cells

With regard to the potential function of Raf-1 in mammalian germ cells, the testis is a site of abundant expression of c-ra/-l mRNAs. Northern blot and in situ hybridization analysis has shown that although c-ra/-l is expressed most abundantly in early pachytene spermatocytes, some transcripts were also detected in germ cells from type A and B spermatogonia through to the round spermatid stage (Wolfes et al., 1989 Wadewitz et al., 1993). 

EXPRESSION AND FUNCTION OF C-MOSIN MAMMALIAN GERM CELLS... 

Mammalian germ cell cytogenetic assay [OECD 483] /... 

For further screening of the most crucial chemicals, a mouse test may be necessary. To test whether a chemical is mutagenic in mammalian germ cells, a specific-locus... 

The specific-locus method is particularly useful in making comparisons of the effects of dose, dose fractionation, sex, cell stage, and other factors on the mutational response in mammalian germ cells, as well as comparisons of the relative responses to different chemicals. Most of what is known about the induction of gene mutations and small deficiencies in germ cells of mammals by radiation and chemicals has been learned in such comparative studies. 

Sega, G.A. Molecular dosimetry of chemical mutagens. Measurement of molecular dose and ENA repair in mammalian germ cells. Mutat. Res. 38 317-326, 1976. 

Sega, G.A., and R.E. Sotomayor. Unscheduled DNA synthesis in mammalian germ cells. Its potential use in mutagenicity testing, pp. 421-445. In F.J. de Serres and A. Hollaender, Eds. Chemical Mutagens Principles and Methods for Their Detection. Vol. 7. New York Plenum Press, 1982. 

Bekaert S, Derradji H, Baatout S (2004), Telomere biology in mammalian germ cells and during development, Dev. Biol. 274 15-30. 

Bentley KS, Sarrif AM, Cimino MC, Auletta AE. 1994. Assessing the risk of heritable gene mutation in mammals Drosophila sex-linked recessive lethal test and tests measuring DNA damage and repair in mammalian germ cells. Environ Mol Mutagen 23 3-11. 

Denk, J.R. 1975. Effects of GB on Mammalian Germ Cells and Reproductive Parameters. EB-TR-74087. AD-A006503. Edgewood Arsenal, Aberdeen Proving Ground, Edgewood, Md. 

Assays for chromosomal aberrations In vitro cytogenetic In vivo cytogenetic Micronucleus Dominant lethal Heritable translocation Mammalian germ cell cytogenetic... 

Adler ID, Shelby MD, Boorman J, et al. (1994) Summary report of the working group on mammalian germ cell tests. Mutation Research 312 313-318. 

The overall findings from in vivo germinal cell assays suggest that mercury compounds are clastogenic for mammalian germ cells. However, the apparent differences in species sensitivity and, in some cases, strain sensitivity preclude an extrapolation of the relevance of these findings to humans. Refer to Table 2-11 for a further summary of these results. 

Parmentier, M., Libert, F., Schurmans, S., Schiffmann, S., Lefort, A., Eggerickx, D., Ledent, C., Mollereau, C., Gerard, J., Perret, A., Grootegoed, G., and Vassart, G. (1992). Expression of members of the putative olfactory receptor gene family in mammalian germ cells. Nature 555 453-455. 

Russo, A. (2000). In vivo cytogenetics Mammalian germ cells. Mutat Res 455, 167-189. 

Denk JR (1975). Effect of GB on mammalian germ cells and reproductive parameters, Final report EB-TR-74087, AD-A006503. Aberdeen Proving Ground, Fort Detrick, MD, USA US Army Medical Research and Development Command. 

DNA material is found in chromosomes. Eukaryotic (higher level cells) chromosomes are each made of a single strand of DNA and several different kinds of proteins (Hale et al., 1995). These chromosomes exist in pairs (said to be diploid), except in some lower forms of algae or fungi that have single sets of chromosomes only (said to be haploid). Mammalian germ cells are also haploid. Some... 

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