Harnessing Transcription Factors as Potential Tools to Enhance Grain Size Under Stressful Abiotic Conditions in Cereal Crops

Abstract

Predicted climate change is widely cited to significantly reduce yields of the major cereal crop species in a period where demand is rapidly rising due to a growing global population. This requires exhaustive research to develop genetic resources in order to address the expected production deficiencies which will largely be driven by abiotic stress. Modification of multiple genes is an approach that can address the predicted challenges; however, it is time-consuming and costly to modify multiple genes simultaneously. Transcription factors represent a group of proteins regulating multiple genes simultaneously and are therefore promising targets to concurrently improve multiple traits concurrently, such as abiotic stress tolerance and grain size (a contributor to yield). Many studies have identified the complex role that transcription factors of multiple families have contributed toward abiotic stress tolerance or grain size, although research addressing both simultaneously is in its infancy despite its potential significance for cereal crop improvement. Here we discuss the potential role that transcription factors may contribute toward improving cereal crop productivity under adverse environmental conditions and offer research objectives that need to be addressed before the modification of transcription factors becomes routinely used to positively manipulate multiple target traits.

Stable sorghum grain quality QTL were identified using SC35 × RTx430 mapping population

“…Candidate gene analysis was conducted within 200‐kb genomic span centering the QTL peaks to locate and analyze genes in these QTL hotspots. Most of the identified genes were transcription factors related to cell division, cell expansion, and cellular transport (Figure 5a,b), which are related to dry matter (protein, carbohydrates, and lipids) accumulation in cereal grains (Tosi et al., 2009; Watt et al., 2020). Transcription factors such as TaNAC019 in wheat ( Triticum aestivum L.) (Gao et al., 2021) and OsNAC20 and OsNAC26 in rice (Wang et al., 2020) were found to coordinately regulate both protein and starch accumulation in the grain.…”

Chromosome-scale assembly of the African yam bean genome

“…The encoding product of these common bean candidate genes were similarly involved in regulation of seed development 68 , seed/fruit size 69 , seed size [70][71][72][73] , grain shape 64,65 , and grain size 74,75 . The mechanism regulating seed traits in AYB needs further exploration.…”

“…Similarly, Olomitutu et al (2022) 57 reported nine candidate genes in common bean by blasting SNPtag of SNP 29420736-57-G/T in legume information system database 67 . The encoding product of these common bean candidate genes were similarly involved in regulation of seed development 68 , seed/fruit size 69 , seed size 70–73 , grain shape 64,65 , and grain size 74,75 . The mechanism regulating seed traits in AYB needs further exploration.…”

Genome-wide superior alleles, haplotypes and candidate genes associated with tolerance on sodic-dispersive soils in wheat (Triticum aestivum L.)

“…Similarly, QTS TGW3 on chromosome 6B corresponds to nuclear transcription factor Y sub-unit which is involved in transcription. MYB-type and BHLHdomain transcription factors are involved in tolerance mechanisms of several abiotic stress and usually co-expressed to enhance grain size under abiotic stress in cereal crops (Bhoite et al 2021;Watt 2020;Roy 2015). The MYB-type transcription factor regulated cadmium tolerance by preventing oxidative damage in Arabidopsis (Agarwal et al 2020), and transcript level of MYB-type transcription factor was enhanced in response to drought stress in potato (Shin et al 2011).…”