scholarly journals Molecular cloning and developmental expression patterns of the MyoD and MEF2 families of muscle transcription factors in the carp.

1998 ◽  
Vol 201 (20) ◽  
pp. 2801-2813 ◽  
Author(s):  
A Kobiyama ◽  
Y Nihei ◽  
Y Hirayama ◽  
K Kikuchi ◽  
H Suetake ◽  
...  

cDNA clones encoding the myogenic regulatory factors (MRFs) myogenin, MyoD and myf-5 were isolated by reverse-transcription polymerase chain reaction from larvae and embryos of the common carp (Cyprinus carpio L.). Myocyte-specific enhancer factor 2 (MEF2) cDNAs were identified from a cDNA library from adult carp. Northern blot analysis showed that MyoD, myf-5 and MEF2C transcripts were present in three-somite embryos, whereas myogenin and MEF2A transcripts were not detected until the 15-somite stage. Intense signals of myogenin and MyoD transcripts were observed even in 1-month-old juveniles. Levels of MyoD, myogenin and MEF2A transcripts declined between 1 and 7 months after hatching, and myf-5 gave only a weak signal in the oldest fish. In contrast, levels of MEF2C transcripts were considerably higher in 7-month-old juveniles than in 1-month-old larvae. mRNAs encoding carp myosin heavy chain and -actin were first detected at approximately the time of the first heartbeat, and levels were maximal in juveniles 1 month post-hatching. The relatively high levels of MRF mRNA in juvenile fish probably reflect the recruitment of new muscle fibres from the satellite cell population. It was concluded that the relative importance of the different members of the MyoD and MEF2 families of transcription factors for muscle differentiation changes during ontogeny in the carp.

Development ◽  
2000 ◽  
Vol 127 (17) ◽  
pp. 3703-3713 ◽  
Author(s):  
M. Bouchard ◽  
P. Pfeffer ◽  
M. Busslinger

Pax2 and Pax5 arose by gene duplication at the onset of vertebrate evolution and have since diverged in their developmental expression patterns. They are expressed in different organs of the mouse embryo except for their coexpression at the midbrain-hindbrain boundary (MHB), which functions as an organizing center to control midbrain and cerebellum development. During MHB development, Pax2 expression is initiated prior to Pax5 transcription, and Pax2(−/−) embryos fail to generate the posterior midbrain and cerebellum, whereas Pax5(−/−) mice exhibit only minor patterning defects in the same brain regions. To investigate whether these contrasting phenotypes are caused by differences in the temporal expression or biochemical activity of these two transcription factors, we have generated a knock-in (ki) mouse, which expresses a Pax5 minigene under the control of the Pax2 locus. Midbrain and cerebellum development was entirely rescued in Pax2(5ki/5ki) embryos. Pax5 could furthermore completely substitute for the Pax2 function during morphogenesis of the inner ear and genital tracts, despite the fact that the Pax5 transcript of the Pax2(5ki)allele was expressed only at a fivefold lower level than the wild-type Pax2 mRNA. As a consequence, the Pax2(5ki)allele was able to rescue most but not all Pax2 mutant defects in the developing eye and kidney, both of which are known to be highly sensitive to Pax2 protein dosage. Together these data demonstrate that the transcription factors Pax2 and Pax5 have maintained equivalent biochemical functions since their divergence early in vertebrate evolution.


2017 ◽  
Author(s):  
E Perea-Atienza ◽  
S.G. Sprecher ◽  
P Martínez

ABSTRACTBackgroundThe basic Helix loop helix (bHLH) family of transcription factors is one of the largest superfamilies of regulatory transcription factors and are widely used in eukaryotic organisms. They play an essential role in a range of metabolic, physiological, and developmental processes, including the development of the nervous system (NS). These transcription factors have been studied in many metazoans, especially in vertebrates but also in early branching metazoan clades such as the cnidarians and sponges. However, currently very little is known about their expression in the most basally branching bilaterian group, the xenacoelomorphs. Recently, our laboratory has characterized the full complement of bHLH in the genome of two members of the Xenacoelomorpha, the xenoturbellidXenoturbella bockiand the acoelSymsagittifera roscoffensis. Understanding the patterns of bHLH gene expression in members of this phylum (in space and time) provides critical new insights into the conserved roles of the bHLH and their putative specificities in this group. Our focus is on deciphering the specific roles that these genes have in the process of neurogenesis.ResultsHere, we analyze the developmental expression of the whole complement of bHLH genes identified in the acoelS. roscoffensis.Based on their expression patterns several members of bHLH class A appear to have specific conserved roles in neurogenesis, while other class A genes (as well as members of other classes) have likely taken on more generalized functions. All gene expression patterns are described in embryos and early juveniles.ConclusionOur results suggest that the main roles of the bHLH genes ofS. roscoffensisare evolutionarily conserved, with a specific subset dedicated to patterning the nervous system: SrAscA, SrAscB, SrHes/Hey, SrNscl, SrSrebp, SrE12/E47 and SrOlig.


Genes ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 588
Author(s):  
He ◽  
Zhou ◽  
Ding ◽  
Teng ◽  
Yan ◽  
...  

The MEF2 (myocyte enhancer factor 2) family belongs to the MADS-box superfamily of eukaryotic transcription factors. The vertebrate genes compose four distinct subfamilies designated MEF2A, -B, -C, and -D. There are multiple mef2 genes in the common carp (Cyprinus carpio). So far, the embryonic expression patterns of these genes and the evolution of fish mef2 genes have been barely investigated. In this study, we completed the coding information of C. carpio mef2ca2 and mef2d1 genes via gene cloning and presented two mosaic mef2 sequences as evidence for recombination. We also analyzed the phylogenetic relationship and conserved synteny of mef2 genes and proposed a new evolutionary scenario. In our version, MEF2B and the other three vertebrate subfamilies were generated in parallel from the single last ancestor via two rounds of whole genome duplication events that occurred at the dawn of vertebrates. Moreover, we examined the expression patterns of C. carpio mef2 genes during embryogenesis, by using whole-mount in situ hybridization, and found the notochord to be a new expression site for these genes except for mef2ca1&2. Our results thus provide new insights into the evolution and expression of mef2 genes.


2005 ◽  
Vol 37 (11) ◽  
pp. 728-736 ◽  
Author(s):  
Bao-Long Niu ◽  
Zhi-Qi Meng ◽  
Yue-Zhi Tao ◽  
Shun-Lin Lu ◽  
Hong-Biao Weng ◽  
...  

Abstract We have identified Bombyx mori transformer-2 gene (Bmtra-2) cDNA by blasting the EST database of B. mori. It was expressed in the whole life of the male and female silkworm and was observed as a band of 1.3 kb by Northern blot analysis. By comparing corresponding ESTs to the Bmtra-2 DNA sequence, it was revealed that there were eight exons and seven introns, and all splice sites of exons/introns conformed to the GT/AG rule. Bmtra-2 pre-mRNA can produce multiple mRNAs encoding six distinct isoforms of BmTRA-2 protein using an alternative splicing pathway during processing. Six types of Bmtra-2 cDNA clones were identified by reverse transcription-polymerase chain reaction. All isoforms of BmTRA-2 protein contain two arginine/serine-rich domains and one RNA recognition motif, showing striking organizational similarity to Drosophila TRA-2 proteins.


2004 ◽  
Vol 17 (9) ◽  
pp. 986-998 ◽  
Author(s):  
Satsuki Fujiwara ◽  
Noriko Tanaka ◽  
Takashi Kaneda ◽  
Seiji Takayama ◽  
Akira Isogai ◽  
...  

Incompatible strains of Acidovorax avenae elicit an immune response in cultured rice cells, with immunity specifically induced by the flagellin of the incompatible strain. To identify genes regulated by flagellin perception signaling in cultured rice cells, gene expression patterns were analyzed with rice cDNA microarrays, including 3,353 independent rice cDNA clones. In all, 131 genes were differentially expressed between incompatible and compatible interactions. K-means clustering showed that 94 genes were upregulated and 32 genes were downregulated during incompatible interactions, whereas only 5 genes were upregulated during compatible interactions. Among the 126 genes that were up- or downregulated during incompatible interactions, expression of 46 genes was decreased when cultured rice cells were inoculated with a flagellin-deficient incompatible strain (Δfla1141-2), indicating that approximately 37% of the 126 genes were directly controlled by flagellin perception. Real-time reverse-transcription polymerase chain reaction analysis using flagellins purified from incompatible or compatible strains was performed to confirm flagellin-regulated expression of candidate genes selected by microarray analysis. Results showed that induction of some genes involved in the immune response is regulated not only by the flagellin perception pathway, but also by another recognition molecule-perception pathway.


2010 ◽  
Vol 239 (12) ◽  
pp. 3446-3466 ◽  
Author(s):  
Karen M. Neilson ◽  
Francesca Pignoni ◽  
Bo Yan ◽  
Sally A. Moody

Development ◽  
1999 ◽  
Vol 126 (11) ◽  
pp. 2539-2550 ◽  
Author(s):  
M. Ogasawara ◽  
H. Wada ◽  
H. Peters ◽  
N. Satoh

The epithelium of the pharynx contributes to the formation of gills in hemichordates, urochordates, cephalochordates and primitive vertebrates, and is therefore a key structure for understanding developmental mechanisms underlying the establishment of chordate body plans. Pax1- and Pax9-related genes encode transcription factors which are expressed in the pharyngeal region of cephalochordates as well as in the vertebrate pharyngeal pouch epithelium that forms the thymus and parathyroid glands. To explore the molecular basis underlying the occurrence and modifications of the pharyngeal epithelium during evolution, we isolated cDNA clones for Pax1- and Pax9-related genes of urochordates (HrPax1/9 of Halocynthia roretzi and CiPax1/9 of Ciona intestinalis) and a hemichordate (PfPax1/9 of Ptychodera flava) from gill cDNA libraries. Each gene is present as a single copy per haploid genome. All of the cDNAs encode typical paired domains and octapeptides but not a homeodomain, as is also true of other Pax1- and Pax9-related genes. Molecular phylogenetic analysis based on comparison of the paired domain amino-acid sequences suggests that HrPax1/9, CiPax1/9 and PfPax1/9 belong to the Pax1/9 subfamily, and that they are descendants of a single precursor of Pax1/Pax9. Screening of HrPax1/9 cDNA clones yielded six different types of transcripts which were generated by alternative splicing. Northern blot, RT-PCR/Southern and in situ hybridization analyses revealed that HrPax1/9, CiPax1/9 and PfPax1/9 are not expressed during early embryogenesis but are expressed in the epithelia of differentiating gills, suggesting that these genes encode gill-specific transcription factors. The Pax1/9 genes therefore might provide the first developmental genetic corroboration of hypotheses of organ-level homology that unifies hemichordates, urochordates and cephalochordates.


1991 ◽  
Vol 2 (4) ◽  
pp. 261-270 ◽  
Author(s):  
S Suzuki ◽  
K Sano ◽  
H Tanihara

To examine the diversity of the cadherin family, we isolated cDNAs from brain and retina cDNA preparations with the aid of polymerase chain reaction. The products obtained included cDNAs for two of three known cadherins as well as eight distinct cDNAs, of which deduced amino acid sequences show significant similarity with the known cadherin sequences. Larger cDNA clones were isolated from human cDNA libraries for six of the eight new molecules. The deduced amino acid sequences show that the overall structure of these molecules is very similar to that of the known cadherins, indicating that these molecules are new members of the cadherin family. We have tentatively designated these cadherins as cadherin-4 through -11. The new molecules, with the exception of cadherin-4, exhibit features that distinguish them as a group from previously cloned cadherins; they may belong to a new subfamily of cadherins. Northern blot analysis showed that most of these cadherins are expressed mainly in brain, although some are expressed in other tissues as well. These findings show that the cadherin family of adhesion molecules is much larger than previously thought, and suggest that the new cadherins may play an important role in cell-cell interactions within the central nervous system.


Author(s):  
Ruben Plöger ◽  
Christoph Viebahn

AbstractThe anterior-posterior axis is a central element of the body plan and, during amniote gastrulation, forms through several transient domains with specific morphogenetic activities. In the chick, experimentally proven activity of signalling molecules and transcription factors lead to the concept of a ‘global positioning system’ for initial axis formation whereas in the (mammotypical) rabbit embryo, a series of morphological or molecular domains are part of a putative ‘three-anchor-point model’. Because circular expression patterns of genes involved in axis formation exist in both amniote groups prior to, and during, gastrulation and may thus be suited to reconcile these models, the expression patterns of selected genes known in the chick, namely the ones coding for the transcription factors eomes and tbx6, the signalling molecule wnt3 and the wnt inhibitor pkdcc, were analysed in the rabbit embryonic disc using in situ hybridisation and placing emphasis on their germ layer location. Peripheral wnt3 and eomes expression in all layers is found initially to be complementary to central pkdcc expression in the hypoblast during early axis formation. Pkdcc then appears — together with a posterior-anterior gradient in wnt3 and eomes domains — in the epiblast posteriorly before the emerging primitive streak is marked by pkdcc and tbx6 at its anterior and posterior extremities, respectively. Conserved circular expression patterns deduced from some of this data may point to shared mechanisms in amniote axis formation while the reshaping of localised gene expression patterns is discussed as part of the ‘three-anchor-point model’ for establishing the mammalian body plan.


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