l(1)pole hole is required maternally for pattern formation in the terminal regions of the embryo

Abstract

Maternal expression of the l(l)pole hole (l(l)ph) gene product is required for the development of the Drosophila embryo. When maternal l(l)ph activity is ab- sent, alterations in the embryonic fate map occur as visualized by the expression of segmentation genes fushi- tarazu and engrailed. If both maternal and zygotic activity is absent, embryos degenerate around 7h of development. If only maternal activity is missing, em- bryos complete embryogenesis and show deletions of both anterior and posterior structures. Anteriorly, structures originating from labral and acron head regions are missing. Posteriorly, abdominal segments A8, 9 and 10, the telson and the proctodeum are missing. Similar pattern deletions are observed in embryos de- rived from the terminal class of female sterile mutations. Thus, the maternal l(l)ph+ gene product is required for the establishment of cell identities at the anterior and posterior poles of the Drosophila embryo.