Is the lepidopteran Z chromosome meiotically inactivated?

DALIKOVA M; PIGOZZI M.I.; TOSCANI, MA; MAREC, F.

Manchester

Congreso; 18th International Chromosome Conference; 2011

International Chromosome and Genome Society (ICGS)

Inactivation of the heterologous sex chromosomes during meiotic prophase I was observed in various species with both the XY (e.g., mouse, opossum, locust, and fruitfly) and WZ (e.g., chicken) systems. In both the systems, the meiotic sex chromosomes inactivation (MSCI) has some similar but also some different features. The MSCI is always associated with epigenetic modifications of chromatin, however, organisms differ in timing and types of the chromatin changes. Regardless some dissimilarities, there is accumulating evidence that MSCI is universal among organisms with heteromorphic sex chromosomes. So far, vast majority of the data on MSCI come from organisms with male heterogamety (XY system). Moths and butterflies (Lepidoptera) represent the largest group of organisms with female heterogamety (i.e., with WZ/ZZ and derived sex chromosome systems) and are thus good candidates for next research on MSCI. In this work, we examined patterns of several histone modifications by immunolabelling of female meiotic cells in the flour moth Ephestia kuehniella. Initial results suggest absence of MSCI in this lepidopteran model.