|
|
||||||||
|
Nodule ParenchymaSpecific Expression of the Sesbania rostrata Early Nodulin Gene SrEnod2 Is Mediated by Its 3' Untranslated RegionRujin Chena,b, David L. Silvera,c, and Frans J. de Bruijna,c,da Michigan State University Department of Energy Plant Research Laboratory, East Lansing, Michigan 48824-1312 b Department of Biochemistry, Michigan State University, East Lansing, Michigan, 48824-1312 c Genetics Program, Michigan State University, East Lansing, Michigan 48824-1312 d Department of Microbiology, Michigan State University, East Lansing, Michigan 48824-1312 Correspondence to: Frans J. de Bruijn, at Michigan State University Department of Energy Plant Research Laboratory, East Lansing, MI 48824-1312., debruijn{at}pilot.msu.edu (E-mail), 517-353-9168 (fax). The early nodulin Enod2 gene encodes a putative hydroxyproline-rich cell wall protein and is expressed exclusively in the nodule parenchyma cell layer. The latter finding suggests that the Enod2 protein may contribute to the special morphological features of the nodule parenchyma and to the creation of an oxygen diffusion barrier. The Enod2 gene of the stem-nodulating legume Sesbania rostrata (SrEnod2) is induced specifically in roots by the plant hormone cytokinin, and this induction occurs at a post-transcriptional level. Here, we characterize the cis determinant(s) in the SrEnod2 locus responsible for nodule parenchymaspecific expression and show that the 3' untranslated region (UTR) of the SrEnod2 gene is both required and sufficient for directing chimeric reporter gene expression in the nodule parenchyma of transgenic Lotus corniculatus plants. Moreover, we show that the SrEnod2 3' UTR does not act as a tissue-specific enhancer element. By conducting a detailed deletion analysis of the 5' and 3' SrEnod2 regions, we delimited the minimal promoter of the SrEnod2 gene, and it appears that the 5' flanking sequences are not essential for nodule parenchymaspecific expression. This finding is in contrast with the report that the 5' upstream region of the soybean Enod2 gene directs nodule parenchymaspecific expression, indicating that different mechanisms may be involved in regulating the expression of these two genes. We definitively demonstrate that the cis element(s) for tissue-specific expression is located within the 3' UTR of a plant nuclear gene.
This article has been cited by other articles:
|
|||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ASPB Publications | THE PLANT CELL | PLANT PHYSIOLOGY | |
|---|---|---|---|