Negative regulation of sexual development by specific interactions of IndB/D proteins with NsdD in Aspergillus nidulans.

Nak-Jung Kwon, 1Dong-Min Han, and Suhn-Kee Chae

Author address: 

BioMed RRC and Dept. of Biochem., Paichai University, Daejeon 302-735 Korea, and 1Division of Biological Science, Wonkwang University, Iksan 570-749, Korea.


A GATA type transcription factor NsdD has been known as a positive regulator of sexual development in A. nidulans. Previously, we isolated two novel proteins, IndB and IndD, that interacted with NsdD by the yeast two-hybrid screening. In vitro and in vivo associations of NsdD with IndB and IndD have been confirmed. Mutated NsdD proteins carrying change in the zinc-finger motif failed to interact with IndB/D, indicating that the intact zinc-finger domain is required for the interactions. Other GATA type proteins of LreA, LreB, and AreA failed to interact with IndB/D, suggesting that NsdD-IndB and -IndD interactions are specific. Northern analysis showed that both of the indB and indD transcripts were highly elevated in veA disruptants, indicating that VeA represses the indB/D gene expression. Overexpression of indB and/or indD strongly inhibited sexual development in veA+ backgrounds. We also identified that IndB/D proteins inhibited DNA bindings of NsdD at putative GATA sites in vitro. Therefore, our results suggest that indB/D function on sexual differentiation negatively via binding to the zinc-finger domain of NsdD to interfere NsdD function, and are regulated by the veA gene, providing a clue of modulating process in sexual development promoted by NsdD and VeA. [Supported by grants from KOSEF]

abstract No: 


Full conference title: 

23rd Fungal Genetics Conference
    • Fungal Genetics Conference 23rd (2002)