The transcription factor T-box 16 (Tbx16, or Spadetail) is an essential regulator of paraxial mesoderm development in zebrafish (Danio rerio). Mesodermal progenitor cells (MPCs) fail to differentiate into trunk somites in tbx16 mutants and instead accumulate within the tailbud in an immature state. However, the mechanisms by which Tbx16 controls mesoderm patterning have remained enigmatic. We describe here the use of photoactivatable morpholino oligonucleotides to determine the Tbx16 transcriptome in MPCs. We identified 124 Tbx16-regulated genes that were expressed in zebrafish gastrulae, including several developmental signaling proteins and regulators of gastrulation, myogenesis and somitogenesis. Unexpectedly, we observed that a loss of Tbx16 function precociously activated posterior hox genes in MPCs, and overexpression of a single posterior hox gene was sufficient to disrupt MPC migration. Our studies support a model in which Tbx16 regulates the timing of collinear hox gene activation to coordinate the anterior-posterior fates and positions of paraxial MPCs.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4990471 | PMC |
http://dx.doi.org/10.1038/nchembio.2124 | DOI Listing |
Sci Rep
December 2024
Centre de Recherche sur le Cancer de L'Université Laval, Centre de Recherche du CHU de Québec-Université Laval (Oncology), 1401, 18e Rue, Québec, QC, G1J 1Z4, Canada.
Hoxa5 plays numerous roles in development, but its downstream molecular effects are mostly unknown. We applied bulk RNA-seq assays to characterize the transcriptional impact of the loss of Hoxa5 gene function in seven different biological contexts, including developing respiratory and musculoskeletal tissues that present phenotypes in Hoxa5 mouse mutants. This global analysis revealed few common transcriptional changes, suggesting that HOXA5 acts mainly via the regulation of context-specific effectors.
View Article and Find Full Text PDFGenes Dev
December 2024
Howard Hughes Medical Institute, Department of Biological Sciences, Columbia University, New York, New York 10025, USA.
The pan-neuronally expressed and phylogenetically conserved CUT homeobox gene orchestrates pan-neuronal gene expression throughout the nervous system of As in many other species, including humans, is encoded by a complex locus that also codes for a Golgi-localized protein, called CASP (Cux1 alternatively spliced product) in humans and CONE-1 ("CASP of nematodes") in How gene expression from this complex locus is controlled-and, in , directed to all cells of the nervous system-has not been investigated. We show here that pan-neuronal expression of CEH-44/CUX is controlled by a pan-neuronal RNA splicing factor, UNC-75, the homolog of vertebrate CELF proteins. During embryogenesis, the locus exclusively produces the Golgi-localized CONE-1/CASP protein in all tissues, but upon the onset of postmitotic terminal differentiation of neurons, UNC-75/CELF induces the production of the alternative CEH-44/CUX CUT homeobox gene-encoding transcript exclusively in the nervous system.
View Article and Find Full Text PDFJ Dev Biol
December 2024
Developmental Biology, Heidelberg University, COS, 69120 Heidelberg, Germany.
Gene regulation depends on the interaction between chromatin-associated factors, such as transcription factors (TFs), which promote chromatin loops to ensure tight contact between enhancer and promoter regions. So far, positive interactions that lead to gene activation have been the main focus of research, but regulations related to blocking or inhibiting factor binding are also essential to maintaining a defined cellular status. To understand these interactions in greater detail, I investigated the possibility of the muscle differentiation factor Mef2 to prevent early Hox factor binding, leading to the proper timing of regulatory processes and the activation of differentiation events.
View Article and Find Full Text PDFClin Breast Cancer
December 2024
Servicio de Oncología Médica, Unidad Médica de Alta Especialidad, Hospital de Ginecología y Obstetricia. Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, México.
Background: Breast cancer (BC) is a multifactorial disease of unknown etiology whose major risk factors are genetic alterations of cell proliferation and migration pathways. HOX transcript antisense RNA gene (HOTAIR) is a long noncoding RNA (lncRNA) related to cell proliferation, progression, invasion, metastasis, and poor survival of multiple cancers, including BC. Controversial results have emerged on the association between breast cancer risk in multiple ethnicities.
View Article and Find Full Text PDFOxid Med Cell Longev
December 2024
Instituto de Investigaciones Biomédicas, Universidad Nacional Autonoma de Mexico, Mexico, Mexico.
Occupational exposure to arsenic (As), cadmium (Cd), and lead (Pb) affects many sectors, necessitating research to understand their transformation mechanisms. In this study, we characterized the process of epithelial-mesenchymal transition (EMT) in a rat hepatic epithelial cell line with decreased expression of catalase and glutamate cysteine ligase catalytic (GCLC) subunit that was exposed to a mixture of As, Cd, and Pb at equimolar occupational exposure concentrations. We evaluated the expression of genes and proteins involved in EMT.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!