染色质可及性在基因转录调控中起着至关重要作用。然而，染色质可及性的调控机制，及其调控玉米关键基因表达和籽粒发育的机制尚不清楚。本研究中，我们分离了一个玉米籽粒突变体，将其命名为dek219，该突变体表现为粉质胚乳和胚停止发育。Dek219编码DICER-LIKE1 (DCL1)蛋白，是一种miRNA生物发生的必需酶。Dek219功能缺失导致大多数miRNAs和组蛋白基因的表达水平显著降低。进一步研究表明，热激转录因子Hsf17-Zm00001d016571模块可能是影响组蛋白基因表达的因素之一。转座酶可及染色质测序分析(ATAC-seq)表明，与野生型(WT)相比，dek219的染色质可及性发生了改变，这可能调控了籽粒发育中关键基因的表达。通过分析WT和dek219之间的差异表达基因(DEGs)和差异可及染色质区域(ACRs)，我们鉴定到119个受染色质可及性调控的候选基因，包括已报道的玉米籽粒发育关键基因。综上所述，这些结果表明Dek219影响染色质可及性和关键基因的表达，是玉米籽粒发育所必需的。

Assessment of yield stability is an important issue for maize (Zea mays L.) cultivar evaluation and recommendation. Manyparametric procedures are available for stability analysis, each of them allowing for different interpretations. The objectiveof the present study was to assess yield stability of maize hybrids evaluated in the National Maize Cultivar Regional Trialsin southwestern China using 20 parametric stability statistics proposed by various authors at different times, and toinvestigate their interrelationships. Two yield datasets were obtained from the 2003 and 2004 national maize cultivarregional trials in southwestern China. A combined analysis of variance, stability statistics, and rank correlations amongthese stability statistics were determined. Effects of location, cultivar, and cultivar by location interaction were highlysignificant (P<0.01). Different stability statistics were used to determine the stability of the studied cultivars. Cultivarmean yield (Y) was significantly correlated to the Lin and Binns stability statistic (LP, r=0.98** and 0.97** for 2003 and 2004trials, respectively) and desirability index (HD, r=0.38 and 0.84** for the 2003 and 2004 trials, respectively). The statisticsLP and HD would be useful for simultaneously selecting for high yield and stability. Based on a principal componentanalysis, the parametric stability statistics grouped as four distinct classes that corresponded to different agronomic andbiological concepts of stability.