First evidence of sex chromosome pre-reduction in male meiosis in the Miridae bugs (Heteroptera)

• Authors: S. Grozeva , S. Nokkala , N. Simov
• Languages of publication: EN

Abstracts

EN

The karyotype and male meiosis of Macrolophus costalis Fieber (Insecta, Heteroptera, Miridae) were studied using C-banding, AgNOR-banding and DNA sequence specific fluorochrome staining. The chromosome formula of the species is 2n=28(24+X1X2X3Y). Male meiotic prophase is characterized by a prominent condensation stage. At this stage, two sex chromosomes, 'X' and Y are positively heteropycnotic and always appeared together, while in autosomal bivalents homologous chromosomes were aligned side by side along their entire length, that is, meiosis is achiasmatic. At metaphase I, 'X' and Y form a pseudobivalent and orient to the opposite poles. At early anaphase I, the 'X' chromosome disintegrates into three separate small chromosomes, X1, X2, and X3. Hence both the autosomes and sex chromosomes segregate reductionally in the first anaphase, and separate equationally in the second anaphase. This is the first evidence of sex chromosome pre-reduction in the family Miridae. Data on C-heterochromatin distribution and its composition in the chromosomes of this species are discussed.

Keywords

EN

CHROMOSOME; HETEROPTERA; MACROLOPHUS COSTALIS; MEIOSIS; MIRIDAE; SEX CHROMOSOME

Discipline

• EXPERIMENTAL_BIOLOGY_&_MEDICINE: EXPERIMENTAL BIOLOGY & MEDICINE

• Publisher: Institute of Systematics and Evolution of Animals, Polish Academy of Sciences
• Journal: Folia Biologica
• Year: 2006
• Volume: 54
• Issue: 1-2
• Pages: 9-12

Contributors

author

S. Grozeva

author

S. Nokkala

author

N. Simov

• Document Type: ARTICLE
• Publication order reference: Snejana Grozeva, Institute of Zoology, Bulgarian Academy of Sciences, 1 Tsar Osvoboditel, 1000 Sofia, Bulgaria