Cloning and expression of circular transcript of mouse growth hormone receptor gene.

Based on reports in the literature and search results on the circBase database, 8 circular transcripts of the mouse growth hormone receptor (GHR) gene were identified. In order to confirm the existence of the circular transcripts of the GHR gene (circGHRs) and to explore their expression patterns, the Kunming mouse (Mus musculus) was used as a research animal. This study detected the existence of circGHRs by RT-PCR amplification and sequencing, one of which was selected as circGHR for detailed analysis. The circular structure of circGHR was confirmed by RNase R treatment and reverse transcription. The spatiotemporal expression of circGHR and GHR mRNA was analyzed by qRT-PCR. The results showed that the full length of mouse circGHR was 820 nt, which was formed by circularization of exons 2-8 of the transcript of the GHR gene. RNase R tolerance analysis shows that mouse circGHR has the general characteristics of circular molecules and is not easily degraded by RNase R. Compared with oligo-d(T)18 primers, random primers have higher reverse transcription efficiency for circGHR, which further shows that circGHR is a poly(A)-free cyclic structure molecule. Tissue expression profile results show that circGHR is highly expressed in the liver and kidney of 1 week-old and 7-week old Kunming mice, but is low in pectoral muscles and leg muscles. The time-series expression profile of circGHR does not show any significant difference between the liver and pectoral muscle tissue. The circGHR expression in the leg muscle was low before 5 weeks of age but increased after 7 weeks of age. This study confirmed the existence of a circular transcript circGHR of the mouse GHR gene, and initially revealed the expression pattern of circGHR. The results of the study laid a foundation for in-depth developmental studies on the biological functions of the mouse circGHR and its mechanism of action regarding the growth and development of mice.

Effects of Circular RNA of Chicken Growth Hormone Receptor Gene on Cell Proliferation.

Animal growth and development are regulated by neural and endocrine growth axes, in which cell proliferation plays key roles. Recently, many research showed that circular RNAs were involved in hepatocyte and myoblast proliferation. Previously, we identified a circular RNA derived from the chicken GHR gene, named circGHR. However, the function of circGHR is unclear. The objective of this study was to investigate circGHR expression pattern and its roles in cell proliferation. Results indicated that circGHR was a closed-loop structure molecule, and it was richer in the nucleus of hepatocytes and myoblast. Real-time PCR showed that circGHR was increased from E13 to the 7th week in the liver but decreased in the thigh and breast muscle. The CCK-8 assay displayed that circGHR promoted cell proliferation. Simultaneously, the biomarker genes PCNA, CCND1, and CDK2 and the linear transcripts GHR and GHBP were upregulated when circGHR was overexpressed. Altogether, these data exhibited that circGHR could promote cell proliferation possibly by regulating GHR mRNA and GHBP expression.

Identification and characterization of circular RNAs in chicken hepatocytes.

CircRNAs play important roles in chicken's growth. In this context, we studied the expression profiles of circRNAs between the GHR antisense transcript overexpressed and the control groups of chicken hepatocytes by using the deep RNA-sequencing technique to identify the key circRNAs involved in chicken's growth. A total of 4772 circRNAs were detected in both groups and 92 circRNAs displayed significant differential expression between two groups. Reactome pathway analysis on the parental genes of differential circRNAs indicated that most enriched and meaningful 9 pathways were related to "Mitotic G1-G1/S-M phases", and "FGFR2c ligand binding and activation". Additionally, Five exonic circRNAs were confirmed including circGHR separated from GHR. CircGHR developed in HuaiXiang chicken from d 1 to 5 w of age and was expressed at a higher level in the nucleus than in the cytoplasm. Moreover, our results specify 5 circRNAs target sites for microRNA Let-7b that is expected to target GHR mRNA, signifying their potential role in regulating GHR gene expression in chicken.

A genetics laboratory class to analyze early and late feather traits of chicken.

With the implementation of the "Education and Training Program for Outstanding Agricultural and Forestry Talents" in our country, our university established the "Outstanding Class" for students majoring in the animal science. We also carried out a series of educational management and curriculum reforms to cultivate students' systematic model of thinking and the ability of technology innovation. In this paper, we designed a comprehensive experiment that focused on analyzing early and late feather genetic traits of chicken. The students initially observed the phenotype of chickens and gradually were led into genetics analysis. We introduced the breeding practice, and guided the students to use genetic theories to breed chick strains of early and late feather traits. The experiment is not only based on the sex-linkage theory and sex determination mechanism, but also molecular genetics technologies, such as genomic DNA extraction, amplification, enzyme digestion and electrophoresis. Conducting this experiment can enhance students' comprehensive analysis ability and professional skills, as well as be beneficial to cultivate their scientific research interests and curiosity on animal sciences. Thus, we integrated the genetics theories into animal breeding practice that meet the requirement of comprehensive applied talents of animal science specialty. The teaching ideas and methods described in this paper can be applied to other biological experiment teaching practice.