The comprehensive detection of miRNA, lncRNA, and circRNA in regulation of mouse melanocyte and skin development

BACKGROUND: Pigmentation development, is a complex process regulated by many transcription factors during development. With the development of the RNA sequencing (RNA-seq), non-coding RNAs, such as miRNAs, lncRNAs, and circRNAs, are found to play an important role in the function detection of related regulation factors. In this study, we provided the expression profiles and development of ncRNAs related to melanocyte and skin development in mice with black coat color skin and mice with white coat color skin during embryonic day 15 (E15) and postnatal day 7 (P7). The expression profiles of different ncRNAs were detected via RNA-seq and also confirmed by the quantitative real-time PCR (qRT-PCR) method. GO and KEGG used to analyze the function the related target genes. RESULTS: We identified an extensive catalogue of 206 and 183 differently expressed miRNAs, 600 and 800 differently expressed lncRNAs, and 50 and 54 differently expressed circRNAs, respectively. GO terms and pathway analysis showed the target genes of differentially expressed miRNA and lncRNA. The host genes of circRNA were mainly enriched in cellular process, single organism process. The target genes of miRNAs were mainly enriched in chromatin binding and calcium ion binding in the nucleus. The function of genes related to lncRNAs are post translation modification. The competing endogenous RNA (ceRNA) network of lncRNAs and circRNAs displays a complex interaction between ncRNA and mRNA related to skin development, such as Tcf4 , Gnas , and Gpnms related to melanocyte development. CONCLUSIONS: The ceRNA network of lncRNA and circRNA displays a complex interaction between ncRNA and mRNA related to skin development and melanocyte development. The embryonic and postnatal development of skin provide a reference for further studies on the development mechanisms of ncRNA during pigmentation.

Skin development in 14 to 60-day-old Guinea pig fetus / Desarrollo de la piel del feto de conejillo de indias de 14 a 60 días

To contribute knowledge of an important experimental model for studies on skin embryology, a study was carried out to describe the morphological events of the skin during the intrauterine life of Cavia porcellus from the 10th to the 60th day of gestation. Embryos and fetuses were dissected, and the skin of the nasal, cranial, lumbar and anal regions was processed byoptical microscopy. At 30 days the first hairs, called lanugos, were observed in the cranial region. The morphological description showed that a few days can make a great difference in development.

Con el objetivo de contribuir al conocimiento de un importante modelo experimental para estudios sobre embriología de la piel, se llevó a cabo un estudio para describir los eventos morfológicos de la piel durante la vida intrauterina de Cavia porcellus desde el día 10 hasta el día 60 de gestación. Los embriones y los fetos se disecaron y se procesó la piel de las regiones nasal, craneal, lumbar y anal, mediante microscopía óptica. A los 30 días se observaron los primeros vellos, llamados lanugos, en la región craneal. La descripción morfológica mostró que unos pocos días pueden marcar una gran diferencia en el desarrollo.

Stem cells in embryonic skin development

The skin is a complex stratified organ which acts not only as a permeability barrier and defense against external agents, but also has essential thermoregulatory, sensory and metabolic functions. Due to its high versatility and activity, the skin undergoes continuous self-renewal to repair damaged tissue and replace old cells. Consequently, the skin is a reservoir for adult stem cells of different embryonic origins. Skin stem cell populations reside in the adult hair follicle, sebaceous gland, dermis and epidermis. However, the origin of most of the stem cell populations found in the adult epidermis is still unknown. Far more unknown is the embryonic origin of other stem cells that populate the other layers of this tissue. In this review we attempt to clarify the emergence, structure, markers and embryonic development of diverse populations of stem cells from the epidermis, dermis and related appendages such as the sebaceous gland and hair follicle.

Comparison of bone morphogenetic protein receptors expression in the fetal and adult skin

Wounds on fetal skin can be repaired without leaving scars until the second trimester, but after this period, skin wounds leave scars as in adults. It's known that certain growth factors such as TGF-beta, and bFGF are present at a very low levels during wound repair in fetal skin. These low levels of growth factors minimize inflammatory response and fibroblast proliferation at the wound site, which in turn inhibit collagen synthesis, and thus, allows scarless wound healing. Recently bone morphogenetic proteins (BMPs), one of the TGF-beta superfamily members, have been studied in the wound healing process. According to several studies, BMPs are related to the differentiation and growth of epithelial and mesenchymal cells, but the precise functions of BMPs and of BMP receptors on skin wound healing have not been elucidated. In this study, we investigated the expression pattern of BMP receptors in fetal skin during the second trimester and in adult skin by immunohistochemical staining and RT-PCR. BMP receptors were detected on the suprabasal epithelial cells and in the hair follicles in adult skin, but were not defected in the fetal skin except for the hair follicles. This was confirmed by confirming mRNA levels of BMP receptors by RT-PCR in both adult and fetal skins. In conclusion, BMPs and BMP receptors seem to be related to fetal and adult wound healing, and low levels of BMPs and BMP receptors during the second trimester seem to contribute to scarless wound healing in the fetus, as is TGF-beta during the second trimester.

Desenvolvimento embriológico da pele humana: análise histológica e revisäo da literatura / Skin embriology: histological analysis and review of literature

A histopatologia representa um recurso diagnóstico fundamental na dermatologia. Entretanto, a grande variedade de entidades nosológicas que acometem a pele, principalmente na faixa etária pediátrica, torna complexa a formaçäo de um profissional treinado para o diagnóstico anatomopatológico em pele, o dermatopatologista, exigindo o conhecimento dos métodos diagnósticos de ponta e de diversas disciplinas básicas, como embriologia e histologia. O objetivo do presente trabalho foi estudar a embriologia do tegumento por meio da avaliaçäo histógica de amostras da pele da regiäo interna da coxa direita, coletadas de fetos e natinortos submetidos a autópsia no Hospital de Clínicas de Curitiba da Universidade Federal do Paraná (UFPR). Os resultados foram descritos por meio de fotomicrografias e comparados com dados de literatura