Functional analysis of the Arabidopsis INDETERMINATE1-like family of zinc finger proteins

• Applicant: Privatdozent Dr. Thomas Merkle
• Subject Area: Plant Cell and Developmental Biology
• Term: from 2002 to 2005
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5388472

cDNAs encoding the zinc finger proteins IDL1 (ID1-like 1) and IDL2 were isolated in a screen for proteins that interact with the Arabidopsis nuclear export receptor XPO1. They contain both, nuclear localisation and nuclear export signals and thus are shuttle proteins. Arabidopsis IDL proteins belong to a family consisting of 11 members that show very high degree of identity within their zinc finger domains and within the adjacent regions. They exhibit the same high degree of identity with the INDETERMINATE 1 (ID1) protein that is implicated in the transition to flowering in maize. We want to analyse the function of the Arabidopsis IDL genes in development and in floral signaling. T-DNA insertion lines for six of the 11 IDL genes were identified. The homozygous lines will be used for phenotypic analyses, physiological and genetic experiments including expression profiling and cross-complementation. IDL1 and IDL2 constitute putative transcription factors that accumulate in the nucleus in Arabidopsis and in tobacco protoplasts. Like the maize ID1 gene, IDL1 and IDL2 genes are expressed only in leaves. Of particular interest will be the role of regulated nucleocytoplasmic shuttling of the IDL proteins for their function in planta.

• DFG Programme: Research Grants