Molecular and cytological characterization of ZTL in Ipomoea nil

Abstract

The ZEITLUPE (ZTL) protein is involved in the control of circadian period, hypocotyl elongation and flowering time in Arabidopsis thaliana. The aim of the present work was the identification of the InZTL gene and localization of its mRNA in the model short-day plant Ipomoea nil. The deduced InZTL protein of 622 amino acid residues contained a LOV domain at the N-terminal part, followed by an F-box domain and six carboxy terminal kelch repeats. Amino acid sequence of InZTL showed 84 % homology with Mesembryanthemum crystallinum ZTL (McZTL) and 83 % with Arabidopsis thaliana ZTL (AtZTL). Fluorescence in situ hybridization (FISH) to InZTL mRNA showed its high accumulation in the vascular bundles as well in the guard cells of the cotyledon. Immunolocalization of ZTL protein indicated a similar distribution pattern of ZTL protein as InZTL mRNAs. © Springer Science+Business Media B.V. 2009.