Achiasmatic male meiosis in Cimex sp. (Heteroptera, Cimicidae)
نویسنده
چکیده
Chromosomes and their behaviour in spermatogenesis in Cimex species (Heteroptera, Cimicidae) from a bat species Myotis emarginatus were studied by using both a conventional staining method and sequence-specific fluorochromes CMA3 and DAPI. Spermatogonial metaphase revealed 28 autosomes, one large Y chromosome and four small X chromosomes. The Y was almost fully C-band positive as well as most telomeres of autosomes. The same regions appeared to be CMA3 and DAPI positive, indicating that in heterochromatin GC-rich clusters are dispersed within AT-rich repeats. In meiosis homologous chromosomes in bivalents are physically associated with one or seldom two sites or collochores, i.e. meiosis is achiasmatic. In MI cells chromosomes in bivalents were aligned in parallel, but at early AI bivalents open out and chromosomes move to the poles one telomere foremost. Meiosis is post-reductional for the sex chromosomes.
منابع مشابه
Bed bug cytogenetics: karyotype, sex chromosome system, FISH mapping of 18S rDNA, and male meiosis in Cimex lectularius Linnaeus, 1758 (Heteroptera: Cimicidae)
Bugs (Insecta: Heteroptera) are frequently used as examples of unusual cytogenetic characters, and the family Cimicidae is one of most interest in this respect. We have performed a cytogenetic study of the common bed bug Cimex lectularius Linnaeus, 1758 using both classical (Schiff-Giemsa and AgNO3-staining) and molecular cytogenetic techniques (base-specifi c DAPI/CMA3 fl uorochromes and FISH ...
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