PdWND3A, a wood-associated NAC domain-containing protein, affects lignin biosynthesis and composition in Populus

Abstract

BackgroundPlant secondary cell wall is a renewable feedstock for biofuels and biomaterials production. Arabidopsis VASCULAR-RELATED NAC DOMAIN (VND) has been demonstrated to be a key transcription factor regulating secondary cell wall biosynthesis. However, less is known about its role in the woody species.ResultsHere we report the functional characterization of Populus deltoides WOOD-ASSOCIATED NAC DOMAIN protein 3 (PdWND3A), a sequence homolog of Arabidopsis VND4 and VND5 that are members of transcription factor networks regulating secondary cell wall biosynthesis. PdWND3A was expressed at higher level in the xylem than in other tissues. The stem tissues of transgenic P. deltoides overexpressing PdWND3A (OXPdWND3A) contained more vessel cells than that of wild-type plants. Furthermore, lignin content and lignin monomer syringyl and guaiacyl (S/G) ratio were higher in OXPdWND3A transgenic plants than in wild-type plants. Consistent with these observations, the expression of FERULATE 5-HYDROXYLASE1 (F5H1), encoding an enzyme involved in the biosynthesis of sinapyl alcohol (S unit monolignol), was elevated in OXPdWND3A transgenic plants. Saccharification analysis indicated that the rate of sugar release was reduced in the transgenic plants. In addition, OXPdWND3A transgenic plants produced lower amounts of biomass than wild-type plants.ConclusionsPdWND3A affects lignin biosynthesis and composition and negatively impacts sugar release and biomass production.

Transcriptional and Post-transcriptional Regulation of Lignin Biosynthesis Pathway Genes in Populus

“…Overexpression of PtrWND2B and PtrWND6B in Arabidopsis causes ectopic deposition of secondary cell wall through activation of the lignin, cellulose and xylan biosynthetic genes (Zhong et al, 2010b). In Populus, the transcript of CCoAOMT1 was induced by overexpressing WND3A (Yang et al, 2019). Zhou et al (2014) demonstrated that the promoter of CCoAOMT1 is directly activated by Arabidopsis VND1-5.…”

Transcriptome-wide and expression analysis of the NAC gene family in pepino (Solanum muricatum) during drought stress

“…Likewise, 183 NAC genes were identified in the white pear ( Pyrus bretschneideri ), which were divided into 33 subgroups, out of which the C2f, C72b and C100a subgroups actively responded to drought and low-temperature stress ( Xin et al, 2019 ). With increased research on the biological functions of NAC transcription factors, it has been shown that NAC transcription factors can regulate a wide range of plant life processes including plant growth and development, the growth and senescence of the cell wall and root through plant hormone signaling pathways ( Wei et al, 2018 ; Yongil et al, 2019 ), and improving plant resistance by responding to a variety of abiotic and biological stress factors ( Du et al, 2020 ; Jia et al, 2019 ). In terms of abiotic regulation, the research on the pathways and mechanisms of NAC family genes for abiotic stress has been intensively studied.…”

In silico identification of conserved miRNAs in the genome of fibre biogenesis crop Corchorus capsularis

“…The study revealed that cca-miR4391 and cca-miR11300 might inhibit the 'NAC Domain Containing Protein' whereas cca-miR1536, cca-miR4391 and cca-miR8689 might cleave the 'S-adenosyl-l-Met-dependent methyl transferase'. Secondary cell wall formation associated NAC protein and its functional homologues are crucial regulatory points that turn on a subset of transcription factors which also directly activate the expression of SCW biosynthetic genes [28,29]. The diverse variety of Cleavage Lignin biosynthesis process [28,29] Secondary cell wall formation [28,29] S-adenosyl-L-Met-dependent methyl transferase cca-miR1536, cca-miR4391, cca-miR8689…”

“…All of the gene targets were cross checked where four gene targets were found as the common target for the five putative miRNAs, and those targets were also highly abundant in the target pool ('Leucine-rich repeat family protein; 13 times', 'Transposable element gene; 87 times', 'Protein kinase superfamily protein; 17 times', 'Pentatricopeptide repeat superfamily protein; 9 times'). Comprehensive literature studies were employed to find out the involvement of predicted gene targets in different biological process.There were few gene targets which were found to be directly or indirectly involved with the lignin biosynthesis and secondary wall biogenesis (Table 3) [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44]. The functions of the common gene targets were also described in Table 3.…”