Zeng Fangqin, Biligetu Bill, Coulman Bruce, Schellenberg Michael P, Fu Yong-Bi
Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK S7N 5A8, Canada.
Swift Current Research and Development Center, Agriculture and Agri-Food Canada, Box 1030, Swift Current, SK S9H 3X2, Canada.
Genes (Basel). 2017 Oct 25;8(11):291. doi: 10.3390/genes8110291.
Crested wheatgrass ( L.) breeding programs aim to develop later maturing cultivars for extending early spring grazing in Western Canada. Plant maturity is a complex genetic trait, and little is known about genes associated with late maturity in this species. An attempt was made using RNA-Seq to profile the transcriptome of crested wheatgrass maturity and to analyze differentially expressed genes (DEGs) between early and late maturing lines. Three cDNA libraries for each line were generated by sampling leaves at the stem elongation stage, spikes at the boot and anthesis stages. A total of 75,218,230 and 74,015,092 clean sequence reads were obtained for early and late maturing lines, respectively. De novo assembly of all sequence reads generated 401,587 transcripts with a mean length of 546 bp and length of 691 bp. Out of 13,133 DEGs detected, 22, 17, and eight flowering related DEGs were identified for the three stages, respectively. Twelve DEGs, including nine flowering related DEGs at the stem elongation stage were further confirmed by qRT-PCR. The analysis of homologous genes of the photoperiod pathway revealed their lower expression in the late maturing line at the stem elongation stage, suggesting that their differential expression contributed to late maturity in crested wheatgrass.
扁穗冰草（L.）育种计划旨在培育晚熟品种，以延长加拿大西部早春放牧期。植物成熟度是一个复杂的遗传性状，对于该物种中与晚熟相关的基因了解甚少。本研究尝试利用RNA测序技术对扁穗冰草成熟过程的转录组进行分析，并分析早熟和晚熟品系之间的差异表达基因（DEG）。在茎伸长阶段采集叶片、孕穗期和开花期采集穗子，分别为每个品系构建了三个cDNA文库。早熟和晚熟品系分别获得了75,218,230和74,015,092条clean序列 reads。对所有序列 reads进行从头组装，得到401,587个转录本，平均长度为546 bp，N50长度为691 bp。在检测到的13,133个DEG中，三个阶段分别鉴定出22个、17个和8个与开花相关的DEG。通过qRT-PCR进一步验证了12个DEG，其中包括茎伸长阶段的9个与开花相关的DEG。光周期途径同源基因分析表明，它们在茎伸长阶段在晚熟品系中的表达较低，表明它们的差异表达促成了扁穗冰草的晚熟。
