The effect of androgen on wool follicles and keratin production in Hetian sheep

To investigate the optimal androgen concentration for culturing Hetian sheep wool follicle and to detect effects of androgen concentration on wool follicle cell proliferation and apoptosis using immunofluorescence labeling and real-time quantitative fluorescence determinations of wool keratin-associated protein gene expression levels. Wool follicles were isolated by microdissection and wool follicles and skin pieces were cultured in various concentrations of dihydrotestosterone (DHT) in culture medium. Next, daily lengthwise growth measurements of wool follicles were obtained using a microscopic micrometer. Cultured Hetian wool follicles were stained using the SACPIC method to reveal wool follicle structure, while sheep skin slices were used to observe cell proliferation by immunostaining and cell apoptosis using the TUNEL method. At the molecular biological level, keratin-associated protein (Kap) gene expression was studied using wool follicles cultured for various numbers of days in vitro. Effects of androgen concentrations on Hetian wool follicle growth and development were experimentally studied. EdU proliferation assays revealed that androgen promoted cell proliferation within wool follicle dermal papillae. TUNEL apoptosis detection demonstrated that androgen treatment could delay cell apoptosis. Quantitative reverse transcription polymerase chain reaction (qPCR) results demonstrated that gene expression level patterns of Hetian mountain sheep super-high sulfur protein. Kap1.1, KIF1.2, Kap2.12 and Kap4.2 gene expression level of the mountainous experimental group was significantly higher than plains Hetian sheep. An androgen concentration of 100 nM can promote the growth of Hetian wool follicle cells in vitro, resulting in overexpression of some genes of the Kap family.

Effect of Nutritional Restriction on the Hair Follicles Development and Skin Transcriptome of Chinese Merino Sheep

The high concentration of secondary branched wool follicles is a distinctive feature of the Merino sheep. At present, the molecular control of the development and branching of secondary wool follicles (SF) remains elusive. To reveal the potential genes associated with the development of hair follicles, we investigated the characteristics of prenatal and postnatal development of wool follicles, and the transcriptional expression profile in fetuses/lambs from dams under either maternal maintenance or sub-maintenance (75% maintenance) nutrition. The density of SF and the ratio of SF to primary wool follicles (PF) were reduced (p < 0.05) in fetuses from day 105 to 135 of gestation under sub-maintenance nutrition. Differentially expressed genes were enriched in the binding, single-organism process, cellular process, cell and cell part Gene Ontology (GO) functional categories and metabolism, apoptosis, and ribosome pathways. Four candidate genes, SFRP4, PITX1, BAMBI, and KRT16, which were involved in secondary wool follicles branching and development, were identified. Our results indicate that nutritional intervention imposed on pregnant ewes by short-term sub-maintenance nutrition could provide a strategy for the study of wool follicle development. Overall insight into the global gene expression associated with SF development can be used to investigate the underlying mechanisms of SF branching in Merino sheep.

Identification and characterization of circRNAs in the skin during wool follicle development in Aohan fine wool sheep

Background: Aohan fine wool sheep (AFWS) is a historically bred fine wool sheep, cultivated in China. The wool has excellent quality and good textile performance. Investigating the molecular mechanisms that regulate wool growth is important to improve wool quality and yield. Circular RNAs (circRNAs) are non-coding RNAs that are widely expressed, and can act as a competitive endogenous RNAs (ceRNAs) to bind to miRNAs. Although circRNAs have been studied in many fields, research on their activity in sheep wool follicles is limited. To understand the regulation of circRNAs in the growth of fine wool in sheep, we used RNA-seq to identify circRNAs in sheep shoulder skin samples at three developmental stages: embryonic day 90 (E90d), embryonic day 120 (E120d), and at birth (Birth). Results: We identified 8,753 circRNAs and found that 918 were differentially-expressed. We then analyzed the classification and characteristic of the circRNAs in sheep shoulder skin. Using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), we identified the source genes of circRNAs, which were mainly enriched in cellular component organization, regulation of primary metabolic processes, tight junctions, and the cGMP-PKG and AMPK signaling pathways. In addition, we predict interactions between 17 circRNAs and eight miRNAs, using miRanda software. Based on the significant pathways, we speculate that circ_0005720, circ_0001754, circ_0008036, circ_0004032, circ_0005174, circ_0005519, circ_0007826 might play an important role in regulating wool follicle growth in AFWS. Seven circRNAs were randomly selected, and have validated the results of the RNA-seq by qRT-PCR. Conclusion: Our results provide more information about circRNAs in regulating wool follicle development in AFWS, and establish a solid foundation for future research.

Identification and characterization of circRNAs in the skin during wool follicle development in Aohan fine wool sheep

Background: Aohan fine wool sheep (AFWS) is a historically bred fine wool sheep, cultivated in China. The wool has excellent quality and good textile performance. Investigating the molecular mechanisms that regulate wool growth is important to improve wool quality and yield. Circular RNAs (circRNAs) are non-coding RNAs that are widely expressed, and can act as a competitive endogenous RNAs (ceRNAs) to bind to miRNAs. Although circRNAs have been studied in many fields, research on their activity in sheep wool follicles is limited. To understand the regulation of circRNAs in the growth of fine wool in sheep, we used RNA-seq to identify circRNAs in sheep shoulder skin samples at three developmental stages: embryonic day 90 (E90d), embryonic day 120 (E120d), and at birth (Birth). Results: We identified 8,753 circRNAs and found that 918 were differentially-expressed. We then analyzed the classification and characteristic of the circRNAs in sheep shoulder skin. Using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), we identified the source genes of circRNAs, which were mainly enriched in cellular component organization, regulation of primary metabolic processes, tight junctions, and the cGMP-PKG and AMPK signaling pathways. In addition, we predict interactions between 17 circRNAs and eight miRNAs, using miRanda software. Based on the significant pathways, we speculate that circ_0005720, circ_0001754, circ_0008036, circ_0004032, circ_0005174, circ_0005519, circ_0007826 might play an important role in regulating wool follicle growth in AFWS. Seven circRNAs were randomly selected, and have validated the results of the RNA-seq by qRT-PCR. Conclusion: Our results provide more information about circRNAs in regulating wool follicle development in AFWS, and establish a solid foundation for future research.

Identification and characterization of circRNAs in the skin during the wool follicle development of Aohan fine wool sheep

Background Aohan fine wool sheep (AFWS) is an early fine wool variety breed cultivated in China. The wool has excellent quality and good textile performance. Investigating the molecular mechanisms that regulate wool growth is important for improving wool quality and yield. Circular RNAs (circRNAs) are non-coding RNAs which are widely expressed and can act as a competitive endogenous RNA (ceRNA) to bind to miRNA. Although circRNA has been studied in many fields, research in sheep wool follicles is limited. To understand the regulation of circRNA in the growth of fine wool sheep, we used RNA-seq to identify circRNAs in sheep shoulder skin at three stages, embryonic day 90 (E90d), embryonic day 120 (E120d), and Birth.Results We identified 8,753circRNAs and found that 1,351 were differentially expressed. We also analyzed the classification and characteristic of the circRNAs in sheep shoulder skin. GO and KEGG were used for source genes of circRNAs, and these were mainly enriched in cellular component organization, regulation of primary metabolic process, tight junctions, and the cGMP-PKG and AMPK signaling pathways. In addition, we predicted interactions between 17 circRNAs and 8 miRNAs using miRanda ( http://www.microrna.org/microrna/home.do ). Based on the significant pathways, we speculate the circ-0005720, circ-0001754, circ-0008036, circ-0004032, circ-0005174, circ-0005519, circ-0007826 may play an important role in regulating wool follicle growth in AFWS. 5 circRNAs were randomly selected to validate the results of the RNA-seq by qRT-PCR.Conclusion Our results provide more information about circRNAs in regulating wool follicle development in AFWS and provide a solid foundation for future experiments.

Skin transcriptome reveals the Periodic changes in genes underlying hair follicle cycling in Cashmere goats

Background Cashmere goats, as an important part of animal husbandry production, make outstanding contributions to animal fiber industry. In recent years, a great deal of research has been done on the molecular regulation mechanism of hair follicle cycle growth. However, there are few reports on the molecular regulation mechanisms of secondary hair follicle growth cycle in cashmere goats. In order to explore the changing regularity of wool follicle cycle and the role of key genes in wool follicle cycle of cashmere goats. we used transcriptome sequencing technique to sequence the skin of Inner Mongolia cashmere goats in different periods, Analyze the variation and difference of genes in the whole hair follicle cycle. And then, we verified the regulation mechanism of cashmere goat secondary hair follicle growth cycle by fluorescence quantitative PCR. Results As the result shows: growth period (March-September), regression period (September-December) and resting period (December-March). The results of differential gene analysis showed that March was considered the beginning of the cycle, and the difference of gene expression was the most significant. Cluster analysis of gene expression in the whole growth cycle further supported the key nodes of the three periods of villus growth, and the differential gene expression of keratin corresponding to the villus growth cycle further supported the results of tissue slices. Quantitative fluorescence analysis showed that KAP3-1, KRTAP 8-1 and KRTAP 24-1 genes had close positive correlation with the growth cycle of cashmere, and their regulation was consistent with the growth cycle of cashmere. However, there was a sequence of expression time, indicating that the results of cycle regulation made the growth of cashmere change. Conclusion The growth cycle of cashmere hair could be divided into three distinct periods: growth period (March-September), regression period (September-December) and resting period (December-March).March was considered the beginning of the cycle, KAP and KRTAP had close positive correlation with the growth cycle of cashmere, and their regulation was consistent with the growth cycle of cashmere. However, there was a sequence of expression time, indicating that the results of cycle regulation made the growth of cashmere change.

Transcriptome Analysis of Improved Wool Production in Skin-Specific Transgenic Sheep Overexpressing Ovine β-Catenin

β-Catenin is an evolutionarily conserved molecule in the canonical Wnt signaling pathway, which controls decisive steps in embryogenesis and functions as a crucial effector in the development of hair follicles. However, the molecular mechanisms underlying wool production have not been fully elucidated. In this study, we investigated the effects of ovine β-catenin on wool follicles of transgenic sheep produced by pronuclear microinjection with a skin-specific promoter of human keratin14 (k14). Both polymerase chain reaction and Southern blot analysis showed that the sheep carried the ovine β-catenin gene and that the β-catenin gene could be stably inherited. To study the molecular responses to high expression of β-catenin, high-throughput RNA-seq technology was employed using three transgenic sheep and their wild-type siblings. These findings suggest that β-catenin normally plays an important role in wool follicle development by activating the downstream genes of the Wnt pathway and enhancing the expression of keratin protein genes and keratin-associated protein genes.