BnaUBP15s positively regulates seed size and seed weight in Brassica napus

Brassica napus(B.napus)is a globally significant oilseed crop,making a substantial contribution to both human oil and livestock feed production.Enhancing seed weight is crucial for improving rapeseed yield;however,only a limited number of seed weight-related genes have been functionally validated in B.napus thus far.UBIQUITINSPECIFIC PROTEASE 15(UBP15)belongs to the ubiquitin protease pathway and plays a maternal role in prolonging seed development in Arabidopsis.The potential utilization of UBP15 for enhancing seed yield in B.napus has remained unexplored until now.In this study,we identified the orthologs of UBP15 in B.napus and investigated its functionality using the CRISPR-Cas9 system.We generated mutant plants with multiple editing types targeting Bnaubp15s and successfully isolated T-DNA-free homozygous mutant lines that exhibited edits across four homologs of BnaUBP15 in T2 generation plants.Our preliminary data demonstrated that mutation of BnaUBP15s significantly reduced seed size,seed weight,and plant height while noticeably increasing the number of primary branches.These findings not only provide crucial evidence for further elucidating the molecular mechanism underlying the regulation of seed weight and size by BnaUBP15s but also offer promising novel germplasm for enhancing plant architecture.

拟南芥突变体sus40-1D的遗传分析与候选基因鉴定

植物器官的大小调控是一个重要的生物学过程,直接影响农作物产量。目前对于植物器官大小调控的研究集中在转录调控、激素信号通路及蛋白质合成与修饰等多个水平和途径,但具体的分子机制并不是很清晰。李云海实验室前期研究发现了一个器官大小的关键调控基因UBIQUITIN SPECIFIC PROTEASE 15(UBP15)/SUPPRESSOR2 OF DA1(SOD2)。sod2-1突变体由于UBP15基因缺失导致器官变小。UBP15作为DA1的底物,其蛋白稳定性受DA1的调节,但其下游通路并不清楚。为了进一步了解UBP15调控器官大小的分子机制,通过EMS诱变筛选分离得到了sod2-1的抑制突变体sus40-1D。sus40-1D sod2-1突变体与sod2-1植株相比,子叶、花瓣和种子面积显著增大。遗传分析表明sus40-1D为显性突变。基因组重测序及连锁分析鉴定出2个与sus40-1D紧密连锁的候选基因:At1g05820和At1g08470。At1g05820的突变发生在内含子区域,而At1g08470的突变发生在外显子区。本研究发现了一个调控器官大小的突变体sus40-1D,对该突变体的进一步研究将有助于解析植物器官大小的调控机制。