Kumar Sonika, Ruggles Ashleigh, Logan Sam, Mazarakis Alora, Tyson Thomas, Bates Matthew, Grosse Clayton, Reed David, Li Zhigang, Grimwood Jane, Schmutz Jeremy, Saski Christopher
Department of Plant and Environmental Sciences, Clemson University, Clemson, SC 29634, USA.
Techshot Inc., Greenville, IN 47124, USA.
Plants (Basel). 2021 Aug 26;10(9):1775. doi: 10.3390/plants10091775.
Somatic embryogenesis-mediated plant regeneration is essential for the genetic manipulation of agronomically important traits in upland cotton. Genotype specific recalcitrance to regeneration is a primary challenge in deploying genome editing and incorporating useful transgenes into elite cotton germplasm. In this study, transcriptomes of a semi-recalcitrant cotton ( L.) genotype 'Coker312' were analyzed at two critical stages of somatic embryogenesis that include non-embryogenic callus (NEC) and embryogenic callus (EC) cells, and the results were compared to a non-recalcitrant genotype 'Jin668'. We discovered 305 differentially expressed genes in Coker312, whereas, in Jin668, about 6-fold more genes (2155) were differentially expressed. A total of 154 differentially expressed genes were common between the two genotypes. Gene enrichment analysis of the upregulated genes identified functional categories, such as lipid transport, embryo development, regulation of transcription, sugar transport, and vitamin biosynthesis, among others. In Coker312 EC cells, five major transcription factors were highly upregulated: , , , , and . In Jin668, , , , and were highly expressed in EC cells. We also found that gene expression of these embryogenesis genes was typically higher in Jin668 when compared to Coker312. We conclude that significant differences in the expression of the above genes between Coker312 and Jin668 may be a critical factor affecting the regenerative ability of these genotypes.
体细胞胚胎发生介导的植物再生对于陆地棉重要农艺性状的遗传操作至关重要。再生的基因型特异性顽拗性是在进行基因组编辑以及将有用的转基因整合到优良棉花种质中的主要挑战。在本研究中，对一个半顽拗型棉花（L.）基因型‘Coker312’在体细胞胚胎发生的两个关键阶段（包括非胚性愈伤组织（NEC）和胚性愈伤组织（EC）细胞）的转录组进行了分析，并将结果与非顽拗型基因型‘晋668’进行了比较。我们在Coker312中发现了305个差异表达基因，而在晋668中，差异表达的基因数量约多6倍（2155个）。两种基因型共有154个差异表达基因。对上调基因的基因富集分析确定了功能类别，如脂质转运、胚胎发育、转录调控、糖转运和维生素生物合成等。在Coker312的胚性愈伤组织细胞中，五个主要转录因子高度上调： 、 、 、 和 。在晋668中， 、 、 和 在胚性愈伤组织细胞中高表达。我们还发现，与Coker312相比，这些胚胎发生基因的基因表达在晋668中通常更高。我们得出结论，Coker312和晋668之间上述基因表达的显著差异可能是影响这些基因型再生能力的关键因素。
