Authors: Katrin Woll Angela Dressel Hajime Sakai HansPeter Piepho Frank Hochholdinger
Publish Date: 2006/08/26
Volume: 113, Issue: 7, Pages: 1305-1315
Abstract
This study comprises a comprehensive gene expression analysis of the root tip specific maize gene ZmGrp3 In the first part of this paper expression of ZmGrp3 was studied in maize inbred lines First RNA in situ hybridization experiments confined the expression of ZmGrp3 to the columella and the epidermis of all embryonic and postembryonic root types Second Northernblot analyses of the maize root initiation mutants rtcs and lrt1 revealed that the ZmGrp3 gene is not expressed prior to root initiation thus providing a novel marker for this developmental process Finally a comprehensive expression profiling in 42 tissues via the Lynx MPSS system revealed almost exclusive expression of ZmGrp3 in maize roots In the second part of this survey ZmGrp3 expression was assayed in maize hybrids In this context a novel approach to quantify allelespecific contribution to gene expression in maize hybrids was developed This assay combines RT–PCR amplification of polymorphisms between two alleles and subsequent quantification of allelespecific gene expression via a combination of didesoxyterminator assays and capillary electrophoresis Allelic expression of the ZmGrp3 gene in six reciprocal hybrids generated from three ZmGrp3 alleles was analyzed via a new statistical mixed model approachWe thank Dr Ron Phillips University of Minnesota for the gift of genomic DNA of oat–maize addition lines Work on this project in FH’s and HPP’s laboratories was supported by the Deutsche Forschungsgemeinschaft DFG framework program SPP1149 “heterosis in plants” Root research in FH’s laboratory is supported by the DFG grant HO2249/4 and the project B16 of the Sonderforschungsbereich 446 “cell behavior in eukaryotes”
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