Molecular cloning and characterization of two novel NAC genes from Mikania micrantha (Asteraceae)

Genet Mol Res. 2012 Dec 17;11(4):4383-401. doi: 10.4238/2012.September.19.3.

Abstract

NAC proteins, which are plant-specific transcription factors, have been identified to play important roles in plant response to stresses and in plant development. The full-length cDNAs that encode 2 putative NAC proteins, designated as MmATAF1 and MmNAP, respectively, were cloned from Mikania micrantha by rapid amplification of cDNA ends. The full-length cDNAs of MmATAF1 and MmNAP were 1329 and 1072 bp, respectively, and they encoded deduced proteins of 260- and 278-amino acid residues, respectively. The proteins MmATAF1 and MmNAP had a calculated molecular mass of 29.81 and 32.55 kDa and a theoretical isoelectric point of 7.08 and 9.00, respectively. Nucleotide sequence data indicated that both MmATAF1 and MmNAP contained 2 introns and 3 exons and that they shared a conserved genomic organization. Multiple sequence alignments showed that MmATAF1 showed high sequence identity with ATAF1 of Arabidopsis thaliana (61%) and that MmNAP showed high sequence identity with NAP of A. thaliana (67%) and CitNAC of Citrus sinensis Osbeck (62%). Phylogenetic analysis showed that the predicted MmATAF1 and MmNAP proteins were classified into the ATAF and NAP subgroups, respectively. Transient expression analysis of onion epidermal cells indicated nuclear localization of both MmATAF1-GFP and MmNAP-GFP fusion proteins. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis indicated that MmATAF1 was expressed in all the tissues tested, but in varying abundance, while MmNAP was specifically expressed in stems, petioles, shoots, and leaves, but not in roots. The transcript levels of MmATAF1 and MmNAP in shoots and in infected stems were induced and strengthened by wounding, exogenous ZnSO(4), abscisic acid, salicylic acid, and Cuscuta campestris infection on the basis of semi-quantitative RT-PCR and real-time PCR analyses, respectively. Collectively, these results indicated that MmATAF1 and MmNAP, besides having roles in M. micrantha adaptation to C. campestris infection and abiotic stresses, also integrated signals derived from both C. campestris infection and abiotic stresses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cell Nucleus / metabolism
  • Cloning, Molecular
  • Gene Expression
  • Gene Expression Regulation, Plant
  • Host-Pathogen Interactions
  • Mikania / genetics*
  • Mikania / metabolism
  • Mikania / microbiology
  • Molecular Sequence Data
  • Organ Specificity
  • Phylogeny
  • Plant Diseases / microbiology
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Plant Stems / genetics*
  • Plant Stems / metabolism
  • Plant Stems / microbiology
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Stress, Physiological
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Xanthomonas campestris / physiology

Substances

  • Plant Proteins
  • Transcription Factors

Associated data

  • GENBANK/EU296447
  • GENBANK/EU296448