Germline Regulation in Flowering Plants (image) University of Leicester Caption Pictured is a confocal image of an Arabidopsis pollen grain showing sperm cell-specific expression of the GFP-tagged plasma membrane protein Generative Cell Specific1 that is required for double fertilisation in flowering plants. The GCS1-GFP fusion protein appears in the periphery of the sperm cell pair (spectacles) present in each pollen grain. The authors show that germ cell division and specification, including the expression of GCS1 are regulated by the germline-specific transcription factor DUO POLLEN 1. Thus DUO1 has an integrative role linking germ cell division and sperm cell differentiation in flowering plants. Credit Image generated by Lynette Brownfield (University of Leicester) Usage Restrictions Must be used with caption and credit. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.