Oral Presentation 16th Asian Conference on Transcription 2019

Male germline specification in flowering plants (1105)

Benjamin Peters 1 , Shiny Varghese 1 , Olivia Kelly 1 , Shereen Asha Murugayah 1 , Stuart Zohrab 1 , David Twell 2 , Lynette Brownfield 1
  1. University of Otago, Dunedin, OTAGO, New Zealand
  2. Genetics, University of Leicester, Leicester, Leicestershire, UK

Development of complex multicellular organisms depends upon the generation of diverse cell types. Asymmetric division, where a mother cell produces daughter cells that are immediately distinct, is a fundamental mechanism for generating cellular diversity. In flowering plants, a critical asymmetric division that leads to distinct daughter cell fate occurs during pollen development. This asymmetric nature of this division is essential for the specification of the male germline. However, little is known about the nature of male germline fate determinants, and how they are unequally distributed into the daughter cells.


While the identity of the germline fate determinants are unknown, they likely lead to the expression of the transcription factor DUO POLLEN1 (DUO1) in the smaller daughter cell soon after the asymmetric division. DUO1 then promotes expression of a diverse array of male germline genes required for sperm cell formation and fertilization. The male germline-specific expression of DUO1 appears to be controlled largely at the transcriptional level. By identifying factors that activate DUO1 expression, we aim to identify the unequally segregated male germline fate determinants.


We have identified a conserved 85 bp region of the DUO1 promoter, called Regulatory Region of DUO1 (ROD1), that replicates the DUO1 expression pattern in pollen. ROD1 contains three cis-regulatory elements that play different roles; one is essential for transcription, one enhances transcription and the other represses transcription. Work is now focused on identifying the transcription factors that bind to these cis-regulatory elements and several candidate transcription factors have been identified.