Developmental analysis of elongation factor-1α expression in transgenic tobacco

Abstract

The developmental regulation of the translational elongation factor EF-1α has been analyzed in tobacco. A gene fusion was constructed consisting of the 5′ and 3′ regions of the tomato genomic clone LeEF-A from the EF-1α gene family and the β-glucuronidase coding region. Analysis of the transgenic plants containing this chimeric gene demonstrated that the tomato LeEF-A flanking sequences were sufficient to confer expression patterns similar to those of the endogenous tobacco EF-1α gene. The patterns of β-glucuronidase activity in this system indicated that during plant growth and development EF-1α is regulated with increased expression corresponding to regions of high protein synthesis, including meristems, rapidly growing tissues, and developing gametophytes. In addition, EF-1α expression responds rapidly to changes in growth patterns induced by hormone treatment. Our results are in agreement with studies in animals indicating that EF-1α expression may be rate limiting for protein synthesis and demonstrate that the analysis of EF-1α is of value for studying interrelationships between protein synthesis and developmental control.