Functional analysis of GhCHS, GhANR and GhLAR in colored fiber formation of Gossypium hirsutum L

Abstract

BackgroundThe formation of natural colored fibers mainly results from the accumulation of different anthocyanidins and their derivatives in the fibers of Gossypium hirsutum L. Chalcone synthase (CHS) is the first committed enzyme of flavonoid biosynthesis, and anthocyanidins are transported into fiber cells after biosynthesis mainly by Anthocyanidin reductase (ANR) and Leucoanthocyanidin reductase (LAR) to present diverse colors with distinct stability. The biochemical and molecular mechanism of pigment formation in natural colored cotton fiber is not clear.ResultsThe three key genes of GhCHS, GhANR and GhLAR were predominantly expressed in the developing fibers of colored cotton. In the GhCHSi, GhANRi and GhLARi transgenic cottons, the expression levels of GhCHS, GhANR and GhLAR significantly decreased in the developing cotton fiber, negatively correlated with the content of anthocyanidins and the color depth of cotton fiber. In colored cotton Zongxu1 (ZX1) and the GhCHSi, GhANRi and GhLARi transgenic lines of ZX1, HZ and ZH, the anthocyanidin contents of the leaves, cotton kernels, the mixture of fiber and seedcoat were all changed and positively correlated with the fiber color.ConclusionThe three genes of GhCHS, GhANR and GhLAR were predominantly expressed early in developing colored cotton fibers and identified to be a key genes of cotton fiber color formation. The expression levels of the three genes affected the anthocyanidin contents and fiber color depth. So the three genes played a crucial part in cotton fiber color formation and has important significant to improve natural colored cotton quality and create new colored cotton germplasm resources by genetic engineering.

The elephant grass (Cenchrus purpureus) genome provides insights into anthocyanidin accumulation and fast growth

“…In addition, the 4Cl family included positively selected genes. In this pathway, chalcone synthase (CHS) plays a core role in naringenin chalcone biosynthesis by condensing 4‐coumaroyl‐CoA, produced via the phenylpropanoid pathway (Gao et al, 2019; Figure 5a). Interestingly, we found that the CHS gene family was expanded and contained 11 copies in Cp, the number of which was higher than the four copies identified in Ca and the one copy in At (Figure 5b).…”

Automatic Identification of Players in the Flavonoid Biosynthesis with Application on the Biomedicinal Plant Croton tiglium

“…LAR channels leucoanthocyanidins into the proanthocyanidin biosynthesis, which is in competition with the anthocyanidin formation catalysed by ANS. There is also a competition between 3-glucosyltransferase (3GT) and ANR for anthocyanidins [ 59 ]. While 3GT generates stable anthocyanins through the addition of a sugar group to anthocyanidins, ANR channels anthocyanidins into the proanthocyanidin biosynthesis.…”

Transcriptome Co-expression Network and Metabolome Analysis Identifies Key Genes and Regulators of Proanthocyanidins Biosynthesis in Brown Cotton

“…Many recent studies have shown that PAs are the main component of pigment deposition in BCF ( Li et al, 2013 ; Feng et al, 2014 ; Xiao et al, 2014 ; Yan et al, 2018 ), and their content reaches typically peaks at 30 DPA ( Feng et al, 2014 ). The biosynthesis of proanthocyanidins precursors regulates the FB pathway to mediate the gene expression of flavonoid metabolism pathway for the development of BCF ( Hua et al, 2007 ; Xiao et al, 2007 , 2014 ; Feng et al, 2013 ; Li et al, 2013 ; Tan et al, 2013 ; Gao et al, 2019 ). Earlier research demonstrated that the synthesis of proanthocyanidins in fiber is the main reason for the shortened elongation period, thus halting the early elongation of BCF ( Qiu, 2004 ).…”

“…Anthocyanidin reductase ( ANR ) is a key structural gene in the PA pathway ( Feng et al, 2014 ). Recently, these two genes, LAR and ANR , have been verified for their transgene functionality, enabling that the development of new colored cotton germplasm has been developed ( Gao et al, 2019 ). In the last decade, transcriptomic or proteomic analyses were used to uncover the PA precursor synthesis pathway involved in fiber pigmentation.…”