Analysis of transcriptome changes in Kmt2d deletion in cardiac mesoderm, anterior heart field precursors and cardiomyocytes

KMT2D is required in the cardiac mesoderm, anterior heart field precursors and cardiomyocytes. Kmt2d deletion in cardiac mesoderm (Mesp1Cre) is embryonic lethal at E10.5 and mutants have hypoplastic hearts; Kmt2d deletion in anterior heart field precursors (Mef2cAHF::Cre) deletion is embryonic lethal at E13.5 and mutants have defects in septation of outflow tract and interventricular septum (IVS); Kmt2d deletion in cardiomyocytes (Tnnt2::Cre) deletion is embryonic lethal at E14.5 and mutants have defects in IVS septation and compact myocardium. The goal of this study is to compare changes in gene expression in these Kmt2d conditional deletion mutants and understand common or distinct pathways dysregulated in absence of KMT2D. Whole genome gene expression analysis was performed on RNA isolated from control and mutant embryonic hearts (or right ventricles and outflow tract for anterior heart field deletion samples). Libraries were prepared using Illumina TruSeq Paired-End Cluster Kit v3, and sequenced with the Illumina HiSeq 2500 system for pair-ended 100 base pairs (PE 100 bp).KMT2D是心脏中胚层、前心区前体细胞以及心肌细胞的必需基因。在心脏中胚层中利用Mesp1Cre驱动敲除Kmt2d会导致胚胎于E10.5时期致死，突变体表现为心脏发育不全；在前心区前体细胞中利用Mef2cAHF::Cre驱动敲除Kmt2d会使胚胎于E13.5时期致死，突变体存在流出道与室间隔（IVS）分隔缺陷；在心肌细胞中利用Tnnt2::Cre驱动敲除Kmt2d会导致胚胎于E14.5时期致死，突变体出现室间隔（IVS）分隔异常与致密心肌层缺陷。本研究旨在对比这三类Kmt2d条件性敲除突变体的基因表达变化，解析缺失KMT2D后失调的共有与特有信号通路。本研究对对照组与突变体胚胎心脏（前心区敲除样本则分别采集右心室与流出道组织）中分离得到的RNA开展全基因组基因表达分析。测序文库采用Illumina TruSeq双端簇制备试剂盒v3构建，并通过Illumina HiSeq 2500测序平台完成双端100碱基对（PE 100 bp）测序。