Transcriptome of LBR-null mouse kidneys

We tested overall gene expression change upon chromatin architecture disruption. RNA-seq was performed using nuclear architecture-disrupted mice carrying a loss-of-function mutation in LBR (Lbric-J/ic-J; LBR-null mice). LBR is an INM protein that tethers heterochromatin to the nuclear envelope whose level is decreased in various aging contexts. Heterozygous LBR-null mice were recovered from cryopreservation at The Jackson Laboratory (C57BL/6J-Lbric-J/J; stock number 000529). After the breeding and genotyping, three homozygous LBR-null mice (Lbric-J/ic-J) and one WT littermate were sacrificed at age of 4 weeks. When they were sacrificed, the right kidneys of mice were flash-frozen, then pulverized and aliquoted for RNA extraction. The LBR-null kidneys were lysed and homogenized in TRI Reagent (R2050, Zymo Research). Trizol RNA miniprep plus kit (R2070, Zymo Research) was used to isolate total RNA. Library preparation with poly(A) selection and 150 bp paired-end sequencing on an Illumina HiSeq were performed by Genewiz (South Plainfield, NJ).本研究检测了染色质结构破坏后的全基因组基因表达变化。实验采用携带核纤层蛋白B受体（Lamin B Receptor, LBR）功能丧失突变的核结构破坏小鼠（Lbr^ic-J/ic-J，即LBR敲除小鼠）开展RNA测序（RNA-seq）。LBR是一种可将异染色质锚定至核被膜的内层核膜（Inner Nuclear Membrane, INM）蛋白，其表达水平在多种衰老相关情境中呈下调趋势。杂合子LBR敲除小鼠购自杰克逊实验室（The Jackson Laboratory），品系为C57BL/6J-Lbr^ic-J/J，货号000529，通过冷冻保存复苏获得。经繁育与基因型鉴定后，于4周龄时处死3只纯合子LBR敲除小鼠（Lbr^ic-J/ic-J）及1只同窝野生型（Wild Type, WT）对照小鼠。处死后立即将小鼠右侧肾脏快速冷冻，随后研磨粉碎并分装，以用于RNA提取。LBR敲除小鼠的肾脏组织在TRI Reagent（R2050，Zymo Research）中裂解并匀浆，随后使用Trizol RNA微量制备试剂盒（R2070，Zymo Research）分离总RNA。由位于新泽西州南普莱菲尔德的Genewiz公司完成文库构建（采用poly(A)富集策略）及Illumina HiSeq平台的150 bp双端测序。