scRNA-seq of fasted or 1 hour refed mouse hypothalamus after 6 weeks of HFD

Immediate Early Genes such as Npas4 are induced as part of the rapid response to environmental stimuli to regulate future transcription. The hypothalamus is made up of distinct neuronal populations and nuclei that regulate homeostatic processes such as POMC neurons that regulate feeding. To date, specific roles of Immediate Early Genes have not been studied in POMC neurons or any other hypothalamic population. Here, we have generated a single cell transcriptomic dataset from the hypothalami of adult male mice that were fed a 60% high fat diet for 6 weeks after Npas4 gene knockout specifically in POMC neurons, with or without a 1 hour refeed after an overnight fast. Our aim was to use this dataset to identify genes that are rapidly regulated by refeeding within 1 hour, as well as potential long-term transcriptomic differences as a result of the Npas4 knockout, in the general POMC neuron population. Adult male mice of either the POMC-CreER (CT) control genotype or POMC-NPAS4 KO (KO) genotype were used. Tamoxifen was administered to all mice at 6 weeks of age, and mice were fed a 60% high fat diet (HFD) from 7 weeks of age. 7 CT and 6 KO mice were used total to generate this dataset. All mice were fasted overnight before their hypothalamus was harvested. 4 CT mice and 3 KO mice were refed for 1 hour after the overnight fast, before harvest, resulting in 13 samples total with minimum n=3 per group (4 refed CT, 3 fasted CT, 3 refed KO, and 3 fasted KO).

即刻早期基因（Immediate Early Genes）如Npas4，作为机体对环境刺激产生快速应答的一部分被诱导表达，以调控后续的转录过程。下丘脑由多种独特的神经元群体与核团组成，负责调控稳态生理过程，例如调控摄食行为的阿片黑素皮质素原（Pro-opiomelanocortin, POMC）神经元。截至目前，即刻早期基因的特异性生理功能尚未在POMC神经元或其他任何下丘脑神经元群体中得到研究。本研究从成年雄性小鼠的下丘脑组织中构建了单细胞转录组数据集，这些小鼠在特异性敲除POMC神经元内的Npas4基因后，被喂食60%高脂饲料持续6周，其中部分小鼠在隔夜禁食后接受了1小时的再喂养，其余小鼠则未进行再喂养。本研究的目标为利用该数据集，在整体POMC神经元群体中，鉴定出1小时内被再喂养快速调控的基因，以及由Npas4基因敲除所导致的潜在长期转录组差异。本研究使用了两种基因型的成年雄性小鼠：POMC-CreER（CT）对照小鼠，以及POMC-NPAS4 KO（KO）基因敲除小鼠。所有小鼠均在6周龄时接受他莫昔芬（Tamoxifen）处理，并于7周龄起喂食60%高脂饲料（high fat diet, HFD）。本数据集共纳入7只CT组小鼠与6只KO组小鼠。所有小鼠在取下丘脑组织前均经历了隔夜禁食。其中4只CT组小鼠与3只KO组小鼠在隔夜禁食后接受1小时再喂养，随后再取下丘脑组织，最终共获得13个样本，各组最小样本量n=3（再喂养CT组4例、禁食CT组3例、再喂养KO组3例、禁食KO组3例）