Stage-specific damage to synaptonemal complexes and metaphase chromosomes induced by X rays in male mouse germ cells
Synaptonemal complexes (SCs) reveal mutagen-induced effects in germ cell meiotic chromosomes. The study was aimed at characterizing relationships between SC and metaphase I chromosome damage following radiation exposure at various stages of spermatogenesis. Male mice were irradiated with doses of 0, 2, or 4 Gy, and spermatocytes were harvested at times consistent with earlier exposures as spermatogonial stem cells, preleptotene cells (premeiotic DNA synthesis), or meiotic prophase cells. After stem-cell exposure, twice as many rearrangements were observed in SCs as in metaphase I chromosomes. Irradiation during premeiotic DNA synthesis resulted in dose-related increases in SC breakage and rearrangements (including novel forms) and in metaphase chromosomal aberrations. Following prophase exposure, various types and levels of SC and metaphase damage were observed. Irradiation of zygotene cells led to high frequencies of chromosome multivalents in metaphase I without a correspondingly high level of damage in preceding prophase SCs. Thus, irradiation of premeiotic and meiotic cells results in variable relationships between SC and metaphase chromosome damage.
- Research Organization:
- Environmental Health Research and Testing, Inc., Research Triangle Park, NC (USA)
- OSTI ID:
- 5733284
- Report Number(s):
- PB-91-182238/XAB; CNN: EPA-68-01-4456
- Resource Relation:
- Other Information: Pub. in Radiation Research, v125 n1 p187-196 Jan 91. Prepared in cooperation with Duke Univ. Medical Center, Durham, NC. Sponsored by Health Effects Research Lab., Research Triangle Park, NC. Genetic Toxicology Div
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CHROMOSOMAL ABERRATIONS
RADIOINDUCTION
SPERMATOCYTES
GENETIC RADIATION EFFECTS
CELL CYCLE
DNA REPLICATION
ELECTRON MICROSCOPY
MICE
MUTAGENESIS
RADIATION DOSES
X RADIATION
ANIMALS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
DOSES
ELECTROMAGNETIC RADIATION
GENETIC EFFECTS
GERM CELLS
IONIZING RADIATIONS
MAMMALS
MICROSCOPY
MUTATIONS
NUCLEIC ACID REPLICATION
RADIATION EFFECTS
RADIATIONS
RODENTS
VERTEBRATES
560120* - Radiation Effects on Biochemicals
Cells
& Tissue Culture