The Myb locus encodes the c-Myb transcription factor involved in controlling a broad variety of cellular processes. Recently, it has been shown that c-Myb may play a specific role in hard tissue formation; however, all of these results were gathered from an analysis of intramembranous ossification. To investigate a possible role of c-Myb in endochondral ossification, we carried out our study on the long bones of mouse limbs during embryonic development. Firstly, the c-myb expression pattern was analyzed by in situ hybridization during endochondral ossification of long bones. c-myb positive areas were found in proliferating as well as hypertrophic zones of the growth plate. At early embryonic stages, localized expression was also observed in the perichondrium and interdigital areas. The c-Myb protein was found in proliferating chondrocytes and in the perichondrium of the forelimb bones (E14.5-E17.5). Furthermore, protein was detected in pre-hypertrophic as well as hypertrophic chondrocytes. Gain-of-function and loss-of-function approaches were used to test the effect of altered c-myb expression on chondrogenesis in micromass cultures established from forelimb buds of mouse embryos. A loss-of-function approach using c-myb specific siRNA decreased nodule formation, as well as downregulated the level of Sox9 expression, a major marker of chondrogenesis. Transient c-myb overexpression markedly increased the formation of cartilage nodules and the production of extracellular matrix as detected by intense staining with Alcian blue. Moreover, the expression of early chondrogenic genes such as Sox9, Col2a1 and activity of a Col2-LUC reporter were increased in the cells overexpressing c-myb while late chondrogenic markers such as Col10a1 and Mmp13 were not significantly changed or were downregulated. Taken together, the results of this study demonstrate that the c-Myb transcription factor is involved in the regulation and promotion of endochondral bone formation.
- MeSH
- biologické markery metabolismus MeSH
- buněčná diferenciace MeSH
- chondrogeneze fyziologie MeSH
- hybridizace in situ MeSH
- končetiny embryologie MeSH
- myši MeSH
- protoonkogenní proteiny c-myb genetika fyziologie MeSH
- umlčování genů MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- apoptóza embryologie MeSH
- inbrední kmeny potkanů genetika MeSH
- končetiny embryologie MeSH
- krysa rodu rattus MeSH
- polydaktylie genetika MeSH
- potkani inbrední SHR genetika MeSH
- potkani Wistar genetika MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- srovnávací studie MeSH
- MeSH
- delfíni MeSH
- končetiny embryologie MeSH
- těhotenství MeSH
- vývoj plodu MeSH
- zvířata MeSH
- Check Tag
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
Acta Universitatis Carolinae. Medica. Monographia ; 1988/125
160 s. : obr., bibliogr.
1. A method for planimetric measurement of areas of standardized dorsoventral projections of embryonal limbs was elaborated. The method permits a quantitative study of the growth of embryonic limbs at early stages of development, since the stage of flat limb bud until the stage at which the external shape of the limb (bending in joint regions and increase in volume) interferes with the simplification of its three-dimensional characteristics to two-dimensional ones of its dorsoventral projection. (Until stage 31-32HH for the chick embryo, see fig. 1 and 2). 2. A method of linear marking was elaborated (fig. 3). The marker proper are India-ink particles suspended in gelatin. Such stained gelatin is spread over a glass carrier (a glass fibre 10-20 microns thick) in the form of a thin film. After drying the fibre is cut in rods of a length desired for the appropriate linear mark. The marks can be introduced into the tissue by a single stab. After the gelatin film had swollen owing to the presence of tissue fluids, it is detached from the carrier surface and the carrier can be removed from the tissue. After the gelatin had been resorbed, a linear mark remains in the tissue. Deformations of the mark line and the scattering of India-ink particles which actually form the mark facilitates the assessment of the growth pattern of the respective marked tissue (see fig. 4-6). 3. During our studies of the differential growth of the wing bud with the method of linear marking the newly coined term "relative tissue shift" had to be specified. That term has been used for designating changes of the mutual position of tissue areas which could not be defined exactly as to their topography within a region or organ (such as the wing bud), showing fluent transitions between one another. If areas with different growth activities occur in the region studied, such areas undergo an uneven increase (differential growth). Thus another factor is added to those operating in the growth process, namely the direction of expansion of the different growing areas of the region studied to one another. The resultant of the mutual ratios of the voluminal growth of the neighbouring tissue areas and the directions of their expansion are the relative tissue shifts in the sense used in our studies.
- MeSH
- abnormality vyvolané léky embryologie MeSH
- adenin analogy a deriváty MeSH
- cévy embryologie růst a vývoj MeSH
- citráty MeSH
- daktinomycin MeSH
- ektoderm MeSH
- končetiny embryologie růst a vývoj MeSH
- křídla zvířecí embryologie MeSH
- kuřecí embryo MeSH
- kyselina citronová MeSH
- mezoderm MeSH
- morfogeneze MeSH
- obratlovci embryologie růst a vývoj MeSH
- teratogeny MeSH
- tkáně embryologie růst a vývoj MeSH
- Check Tag
- kuřecí embryo MeSH
- Konspekt
- Anatomie člověka a srovnávací anatomie
- NLK Obory
- anatomie
- embryologie a teratologie
- cytologie, klinická cytologie
- histologie
- NLK Publikační typ
- studie
