<i>eyes absent</i>in the cockroach panoistic ovaries regulates proliferation and differentiation through ecdysone signalling

AbstractEyes absent (Eya), is a protein structurally conserved from hydrozoans to humans, for which two basic roles have been reported: it can act as a transcription cofactor and as a protein tyrosine phosphatase. Eya was discovered in the flyDrosophila melanogasterin relation to its function in eye development, and the same function was later reported in other insects. Eya is also involved in insect oogenesis, although studies in this sense are limited toD. melanogaster, which has meroistic ovaries, and whereeyamutations abolish gonad formation.In the present work we studied the function ofeyain the panoistic ovary of the cockroachBlattella germanica. We show thateyais essential for correct development of panoistic ovaries. InB. germanica, eyaacts at different level and in a distinct way in the germarium and the vitellarium. In the germarium,eyacontributes to maintain the correct number of somatic and germinal cells by regulating the expression of steroidogenic genes in the ovary. In the vitellarium,eyafacilitates follicle cells proliferation and contributes to regulate the cell program, in the context of basal ovarian follicle maturation. Thus,eya-depleted females ofB. germanicaarrest the growth and maturation of basal ovarian follicles and become sterile.</jats:p