Genome-wide survey identifies TNNI2 as a target of KLF7 that inhibits chicken adipogenesis via downregulating FABP4

E2F transcription factor 5, a new regulator in adipogenesis to mediate the role of Krüppel-like factor 7 in chicken preadipocyte differentiation and proliferation

E2F transcription factor 5 (E2F5) gene is a transcription factor, plays an important role in the development of a variety of cells. E2F5 is expressed in human and mouse adipocytes, but its specific function in adipogenesis is unclear. Krüppel-like factor 7 (KLF7) facilitates proliferation and inhibits differentiation in chicken preadipocytes. Our previous KLF7 chromatin immunoprecipitation-sequencing analysis revealed a KLF7-binding peak in the 3' flanking region of the E2F5, indicating a regulatory role of KLF7 in this region. In the present study, we investigated E2F5 potential role, the overexpression and knockdown analyses revealed that E2F5 inhibited the differentiation and promoted the proliferation of chicken preadipocytes. Moreover, we identified enhancer activity in the 3' flanking region (nucleotides +22661/+22900) of E2F5 and found that KLF7 overexpression increased E2F5 expression and luciferase activity in this region. Deleting the putative KLF7-binding site eliminated the promoting effect of KLF7 overexpression on E2F5 expression. Further, E2F5 reversed the KLF7-induced decrease in preadipocyte differentiation and increase in preadipocyte proliferation. Taken together, our findings demonstrate that KLF7 inhibits differentiation and promotes proliferation in preadipocytes by enhancing E2F5 transcription.

Full-Length Transcriptome Analysis of Skeletal Muscle of Jiangquan Black Pig at Different Developmental Stages

Skeletal muscle grows in response to a combination of genetic and environmental factors, and its growth and development influence the quality of pork. Elucidating the molecular mechanisms regulating the growth and development of skeletal muscle is of great significance to both animal husbandry and farm management. The Jiangquan black pig is an excellent pig breed based on the original Yimeng black pig, importing the genes of the Duroc pig for meat traits, and cultivated through years of scientific selection and breeding. In this study, full-length transcriptome sequencing was performed on three growth stages of Jiangquan black pigs, aiming to study the developmental changes in Jiangquan black pigs at different developmental stages at the molecular level and to screen the key genes affecting the growth of skeletal muscle in Jiangquan black pigs. We performed an enrichment analysis of genes showing differential expression and constructed a protein-protein interaction network with the aim of identifying core genes involved in the development of Jiangquan black pigs. Notably, genes such as TNNI2, TMOD4, PLDIM3, MYOZ1, and MYH1 may be potential regulators of muscle development in Jiangquan black pigs. Our results contribute to the understanding of the molecular mechanisms of skeletal muscle development in this pig breed, which will facilitate molecular breeding efforts and the development of pig breeds to meet the needs of the livestock industry.

The kruppel-like factor (KLF) family, diseases, and physiological events

The Kruppel-Like Factor family of regulatory proteins, which has 18 members, is transcription factors. This family contains zinc finger proteins, regulates the activation and suppression of transcription, and binds to DNA, RNA, and proteins. Klfs related to the immune system are Klf1, Klf2, Klf3, Klf4, Klf6, and Klf14. Klfs related to adipose tissue development and/or glucose metabolism are Klf3, Klf7, Klf9, Klf10, Klf11, Klf14, Klf15, and Klf16. Klfs related to cancer are Klf3, Klf4, Klf5, Klf6, Klf7, Klf8, Klf9, Klf10, Klf11, Klf12, Klf13, Klf14, Klf16, and Klf17. Klfs related to the cardiovascular system are Klf4, Klf5, Klf10, Klf13, Klf14, and Klf15. Klfs related to the nervous system are Klf4, Klf7, Klf8, and Klf9. Klfs are associated with diseases such as carcinogenesis, oxidative stress, diabetes, liver fibrosis, thalassemia, and the metabolic syndrome. The aim of this review is to provide information about the relationship of Klfs with some diseases and physiological events and to guide future studies.

PU.1 interacts with KLF7 to suppress differentiation and promote proliferation in chicken preadipocytes

<p indent="0mm">Krüppel-like factor 7 (KLF7) is a negative regulator of preadipocyte differentiation. Our previous KLF7 ChIP-seq analysis showed that the binding motif of PU.1 was found among the KLF7 binding peaks, indicating that an interaction between KLF7 and PU.1 at preadipocyte gene promoters and other regulatory elements might be common. Here, Co-IP and FRET assays are used to confirm that PU.1 can directly bind to KLF7 and enhance the transcription activity of cyclin-dependent kinase inhibitor 3 ( <italic>CDKN3</italic>), which is a downstream target gene of KLF7. We show that the PU.1 expression level is decreased during preadipocyte differentiation. Furthermore, PU.1 overexpression and knockdown experiments reveal that PU.1 negatively regulates chicken preadipocyte differentiation, as evidenced by appropriate changes in lipid droplet accumulation and altered expressions of PPARγ, FAS, and PLIN. In addition, PU.1 overexpression promotes preadipocyte proliferation, while knockdown of <italic>PU</italic>. <italic>1</italic> inhibits preadipocyte proliferation. We further demonstrate that PU.1 inhibits differentiation and promotes proliferation in preadipocytes, in part by directly interacting with KLF7. </p>.