An Isoform of Eukaryotic Initiation Factor 4E from Chrysanthemum morifolium Interacts with Chrysanthemum Virus B Coat Protein

Aiping Song,Jiafu Jiang,Nianjun Teng,Zuxia Sun,Zhiyong Guan,Wanghuai Lou,Fadi Chen,Sumei Chen,Weimin Fang,Vladimir N Uversky

doi:10.1371/journal.pone.0057229

Aiping Song, Jiafu Jiang + Show 8 more

Open Access

https://doi.org/10.1371/journal.pone.0057229

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Journal: PloS one	Publication Date: Mar 7, 2013
Citations: 15	License type: CC BY 4.0

Affiliation: Nanjing Agricultural University

Abstract

BackgroundEukaryotic translation initiation factor 4E (eIF4E) plays an important role in plant virus infection as well as the regulation of gene translation.Methodology/Principal FindingsHere, we describe the isolation of a cDNA encoding CmeIF(iso)4E (GenBank accession no. JQ904592), an isoform of eIF4E from chrysanthemum, using RACE PCR. We used the CmeIF(iso)4E cDNA for expression profiling and to analyze the interaction between CmeIF(iso)4E and the Chrysanthemum virus B coat protein (CVBCP). Multiple sequence alignment and phylogenetic tree analysis showed that the sequence similarity of CmeIF(iso)4E with other reported plant eIF(iso)4E sequences varied between 69.12% and 89.18%, indicating that CmeIF(iso)4E belongs to the eIF(iso)4E subfamily of the eIF4E family. CmeIF(iso)4E was present in all chrysanthemum organs, but was particularly abundant in the roots and flowers. Confocal microscopy showed that a transiently transfected CmeIF(iso)4E-GFP fusion protein distributed throughout the whole cell in onion epidermis cells. A yeast two hybrid assay showed CVBCP interacted with CmeIF(iso)4E but not with CmeIF4E. BiFC assay further demonstrated the interaction between CmeIF(iso)4E and CVBCP. Luminescence assay showed that CVBCP increased the RLU of Luc-CVB, suggesting CVBCP might participate in the translation of viral proteins.Conclusions/SignificanceThese results inferred that CmeIF(iso)4E as the cap-binding subunit eIF(iso)4F may be involved in Chrysanthemum Virus B infection in chrysanthemum through its interaction with CVBCP in spatial.

Highlights

Eukaryotic translation initiation factor 4E is a protein that plays a major role in the regulation of gene expression at the post-transcriptional level [1]
The cloned CmeIF(iso)4E cDNA consists of 818 bp with a 573 bp open reading frames (ORFs) encoding a 190-amino acid protein
Other studies have shown that eIF4E and eIF(iso)4E both function in the selection of mRNA for translation, but differ in their expression in different tissues and their ability to bind to mRNA cap structures [4], [11]

Summary

Introduction

Eukaryotic translation initiation factor 4E (eIF4E) is a protein that plays a major role in the regulation of gene expression at the post-transcriptional level [1]. EIF4E binds to the mRNA 59 m7G cap structure and brings the mRNA into a complex with other protein synthesis initiation factors and ribosomes, resulting in mRNA circularization and translation initiation [4], [5]. Whereas eIF4E is present in all tissues except the root specialization zones, eIF(iso)4E is abundant in floral tissues and young tissues [11] Differences in their transcription patterns and binding affinities suggest that these isoforms might have complementary biological roles [12]. Eukaryotic translation initiation factor 4E (eIF4E) plays an important role in plant virus infection as well as the regulation of gene translation

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