Achiasmatic male meiosis in Myrmedobia coleoptrata (Fn.) (Heteroptera, Microphysidae)

نویسندگان

  • SEPPO NOKKALA
  • SNEJANA GROZEVA
چکیده

Mitosis and male meiosis were studied in Myrmedobia coleoptrata (Fn.), (Heteroptera, Microphysidae). Spermatogonial metaphase revealed 14 chromosomes (2n=12 + XY). The nucleolar organizing region was found on the X chromosome. No m-chromosomes were present in the complement. Male meiotic prophase was characterized by a prominent condensation stage. At this stage, the sex chromosomes were positively heteropycnotic and appeared as separate univalents, while in autosomal bivalents homologous chromosomes were aligned side by side along their entire length, i.e. meiosis is achiasmatic. Meiosis was prereductional for the autosomes and post-reductional for the X and Y chromosomes. Meiosis was further characterized by non-radial arrangement of chromosomes in metaphase I plate and radial arrangement in metaphase II. Cytological characteristics of achiasmatic meioses and their distribution within Heteroptera are discussed.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Achiasmate male meiosis in two Cymatia species (Hemiptera, Heteroptera, Corixidae)

The karyotype and male meiosis, with a particular focus on the presence or absence of chiasmata between the homologs, were studied in the water boatman species Cymatia rogenhoferi (Fieber) and Cymatia coleoptrata (Fabricius) (Corixidae, Cymatiainae). It is shown that the species have 2n = 33 (28A+2m+X1X2Y) and 2n = 24 (20A+2m+XY) respectively, post-reduction of sex chromosomes, and achiasmate m...

متن کامل

Achiasmatic male meiosis in Cimex sp. (Heteroptera, Cimicidae)

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 t...

متن کامل

Heterochromatin characterization and ribosomal gene location in two monotypic genera of bloodsucker bugs (Cimicidae, Heteroptera) with holokinetic chromosomes and achiasmatic male meiosis.

Members of the family Cimicidae (Heteroptera: Cimicomorpha) are temporary bloodsuckers on birds and bats as primary hosts and humans as secondary hosts. Acanthocrios furnarii (2n=12=10+XY, male) and Psitticimex uritui (2n=31=28+X1X2Y, male) are two monotypic genera of the subfamily Haematosiphoninae, which have achiasmatic male meiosis of collochore type. Here, we examined chromatin organizatio...

متن کامل

The evolution and expression of Drosophila meiosis genes

Drosophila melanogaster is unique amongst model organisms in that males utilize achiasmatic meiosis, where formation of the synaptonemal complex (SC) and recombination are absent. Most organisms require the SC and chiasmata for the successful completion of meiosis and production of viable gametes, making D. melanogaster an ideal system for the study of meiotic variation. Drosophila are not the ...

متن کامل

The significance of cytogenetics for the study of karyotype evolution and taxonomy of water bugs (Heteroptera, Belostomatidae) native to Argentina

Male meiosis behaviour and heterochromatin characterization of three big water bug species were studied. Belostoma dentatum (Mayr, 1863), Belostoma elongatum Montandon, 1908 and Belostoma gestroi Montandon, 1903 possess 2n = 26 + X1X2Y (male). In these species, male meiosis is similar to that previously observed in Belostoma Latreille, 1807. In general, autosomal bivalents show a single chiasma...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2001