THE ROLE OF AURORA KINASE IN THE DEVELOPING MALE GAMETOPHYTE OF MARSILEA VESTITA

Abstract

The development of the male gametophyte of Marsilea vestita occurs via an ordered sequence of cellular events, which result in the formation of 32 motile sperm. The blepharoplast is a subcellular structure that arises de novo at ~3.5 hours following microspore hydration and functions as a microtubule organizing center during the final mitotic division. I investigated the roles of aurora kinases in the formation and maturation of the blepharoplast. Three unique aurora kinase isoforms were found in the transcriptome of the male gametophyte, each with a unique N-terminal sequence and expression pattern. RNAi knockdowns of each isoform resulted in different stages of developmental arrest, and the absence of blepharoplasts, thereby suggesting that each isoform has a unique function. Centrin phosphomimics acted to stabilize centrin, enabling centrin aggregates to form. My results suggest that each isoform of aurora kinase plays an important role in male gametophyte development in Marsilea.