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ParaHox
The ParaHox gene cluster is an array of homeobox genes (involved in morphogenesis, the regulation of patterns of anatomical development) from the Gsx, Xlox ( Pdx) and Cdx gene families. Regulatory gene cluster These genes were first shown to be arranged into a physically-linked chromosomal cluster in amphioxus, an invertebrate with a single member of each of the three gene families. All the ParaHox genes in the amphioxus genome are therefore in the ParaHox gene cluster. In contrast, the human genome has six ParaHox genes ( GSX1, GSX2, PDX1, CDX1, CDX2, CDX4), of which three genes ( GSX1, PDX1 (=IPF1), CDX2) are physically linked to form a human ParaHox gene cluster on chromosome 13. Mice have a homologous ParaHox gene cluster on chromosome 5. The other three human ParaHox genes are remnants from duplicated ParaHox gene clusters that were generated in the 2R genome duplications at the base of vertebrate evolution. Some vertebrates, notably chondrichthyan fish and coel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xlox
PDX1 (pancreatic and duodenal homeobox 1), also known as insulin promoter factor 1, is a transcription factor in the ParaHox gene cluster.Brooke, N. M., Garcia-Fernàndez, J., & Holland, P. W. (1998). The ParaHox gene cluster is an evolutionary sister of the Hox gene cluster. Nature, 392(6679), 920. In vertebrates, Pdx1 is necessary for pancreatic development, including β-cell maturation, and duodenal differentiation. In humans this protein is encoded by the ''PDX1'' gene, which was formerly known as ''IPF1''. The gene was originally identified in the clawed frog ''Xenopus laevis'' and is present widely across the evolutionary diversity of bilaterian animals, although it has been lost in evolution in arthropods and nematodes. Despite the gene name being ''Pdx1'', there is no ''Pdx2'' gene in most animals; single-copy Pdx1 orthologs have been identified in all mammals. Coelacanth and cartilaginous fish are, so far, the only vertebrates shown to have two ''Pdx'' genes, ''Pdx1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pdx (gene Family)
PDX1 (pancreatic and duodenal homeobox 1), also known as insulin promoter factor 1, is a transcription factor in the ParaHox gene cluster.Brooke, N. M., Garcia-Fernàndez, J., & Holland, P. W. (1998). The ParaHox gene cluster is an evolutionary sister of the Hox gene cluster. Nature, 392(6679), 920. In vertebrates, Pdx1 is necessary for pancreatic development, including β-cell maturation, and duodenal differentiation. In humans this protein is encoded by the ''PDX1'' gene, which was formerly known as ''IPF1''. The gene was originally identified in the clawed frog ''Xenopus laevis'' and is present widely across the evolutionary diversity of bilaterian animals, although it has been lost in evolution in arthropods and nematodes. Despite the gene name being ''Pdx1'', there is no ''Pdx2'' gene in most animals; single-copy Pdx1 orthologs have been identified in all mammals. Coelacanth and cartilaginous fish are, so far, the only vertebrates shown to have two ''Pdx'' genes, ''Pdx1'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PDX1
PDX1 (pancreatic and duodenal homeobox 1), also known as insulin promoter factor 1, is a transcription factor in the ParaHox gene cluster.Brooke, N. M., Garcia-Fernàndez, J., & Holland, P. W. (1998). The ParaHox gene cluster is an evolutionary sister of the Hox gene cluster. Nature, 392(6679), 920. In vertebrates, Pdx1 is necessary for pancreatic development, including β-cell maturation, and duodenal differentiation. In humans this protein is encoded by the ''PDX1'' gene, which was formerly known as ''IPF1''. The gene was originally identified in the clawed frog ''Xenopus laevis'' and is present widely across the evolutionary diversity of bilaterian animals, although it has been lost in evolution in arthropods and nematodes. Despite the gene name being ''Pdx1'', there is no ''Pdx2'' gene in most animals; single-copy Pdx1 orthologs have been identified in all mammals. Coelacanth and cartilaginous fish are, so far, the only vertebrates shown to have two ''Pdx'' genes, ''Pdx1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeobox
A homeobox is a Nucleic acid sequence, DNA sequence, around 180 base pairs long, that regulates large-scale anatomical features in the early stages of embryonic development. Mutations in a homeobox may change large-scale anatomical features of the full-grown organism. Homeoboxes are found within genes that are involved in the regulation of patterns of anatomical development (morphogenesis) in animals, fungus, fungi, plants, and numerous single cell eukaryotes. Homeobox genes encode homeodomain protein products that are transcription factors sharing a characteristic protein fold structure that binds DNA to regulate expression of target genes. Homeodomain proteins regulate gene expression and cell differentiation during early embryonic development, thus mutations in homeobox genes can cause developmental disorders. Homeosis is a term coined by William Bateson to describe the outright replacement of a discrete body part with another body part, e.g. antennapedia—replacement of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gsx (gene Family)
The Gsx gene family are a group of genes found in many, but not all, animals. Gsx genes contain a homeobox DNA sequence and code for proteins that act as transcription factors. The human genome has two Gsx genes, called ''GSX1'' and '' GSX2'' (formerly ''GSH1'' and ''GSH2''), while the fruitfly ''Drosophila'' has a single Gsx gene called ''ind''. Vertebrate Gsx genes are implicated in neural patterning. In many animals, Gsx genes can be part of a ParaHox The ParaHox gene cluster is an array of homeobox genes (involved in morphogenesis, the regulation of patterns of anatomical development) from the Gsx, Xlox ( Pdx) and Cdx gene families. Regulatory gene cluster These genes were first shown to ... gene cluster. References {{Transcription factors and intracellular receptors, g3 Developmental genes and proteins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hox Gene
Hox genes, a subset of homeobox, homeobox genes, are a gene cluster, group of related genes that Evolutionary developmental biology, specify regions of the body plan of an embryo along the craniocaudal axis, head-tail axis of animals. Hox proteins encode and specify the characteristics of 'position', ensuring that the correct structures form in the correct places of the body. For example, Hox genes in insects specify which appendages form on a segment (for example, legs, antennae, and wings in fruit flies), and Hox genes in vertebrates specify the types and shape of vertebrae that will form. In segmented animals, Hox proteins thus confer segmental or positional identity, but do not form the actual segments themselves. Studies on Hox genes in ciliated larvae have shown they are only expressed in future adult tissues. In larvae with gradual metamorphosis the Hox genes are activated in tissues of the larval body, generally in the trunk region, that will be maintained through metamorp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CDX2
Homeobox protein CDX-2 is a protein that in humans is encoded by the ''CDX2'' gene. The CDX-2 protein is a homeobox transcription factor expressed in the nuclei of intestinal epithelial cells, playing an essential role in the development and function of the digestive system. ''CDX2'' is part of the ParaHox gene cluster, a group of three highly conserved developmental genes present in most vertebrate species. Together with ''CDX1'' and '' CDX4'', ''CDX2'' is one of three caudal-related genes in the human genome. Function In common with the two other Cdx genes, CDX2 regulates several essential processes in the development and function of the lower gastrointestinal tract (from the duodenum to the anus) in vertebrates. In vertebrate embryonic development, CDX2 becomes active in endodermal cells that are posterior to the developing stomach. These cells eventually form the intestinal epithelium. The activity of CDX2 at this stage is essential for the correct formation of the intest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Developmental Genes And Proteins
Development of the human body is the process of growth to maturity. The process begins with fertilization, where an egg released from the ovary of a female is penetrated by a sperm cell from a male. The resulting zygote develops through mitosis and cell differentiation, and the resulting embryo then implants in the uterus, where the embryo continues development through a fetal stage until birth. Further growth and development continues after birth, and includes both physical and psychological development that is influenced by genetic, hormonal, environmental and other factors. This continues throughout life: through childhood and adolescence into adulthood. Before birth Development before birth, or prenatal development () is the process in which a zygote, and later an embryo, and then a fetus develops during gestation. Prenatal development starts with fertilization and the formation of the zygote, the first stage in embryonic development which continues in fetal developmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coelacanths
Coelacanths ( ) are an ancient group of lobe-finned fish (Sarcopterygii) in the class Actinistia. As sarcopterygians, they are more closely related to lungfish and tetrapods (the terrestrial vertebrates including living amphibians, reptiles, birds and mammals) than to ray-finned fish. The name coelacanth originates from the Permian genus ''Coelacanthus'', which was the first scientifically named genus of coelacanths (in 1839), becoming the type genus of Coelacanthiformes as other species were discovered and named. Well-represented in freshwater and marine deposits from as early as the Devonian period (more than 410million years ago), they were thought to have become extinct in the Late Cretaceous, around 66million years ago. The first living species, ''Latimeria chalumnae'', the West Indian Ocean coelacanth, was described from specimens fished off the coast of South Africa from 1938 onward; they are now also known to inhabit the seas around the Comoro Islands off the east ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondrichthyan
Chondrichthyes (; ) is a class (biology), class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fish'', which have skeletons primarily composed of bone tissue. Chondrichthyes are aquatic animal, aquatic vertebrates with paired fins, paired Nostril, nares, placoid scales, conus arteriosus in the heart, and a lack of operculum (fish), opercula and swim bladders. Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates. The class is divided into two subclasses: Elasmobranchii (sharks, Batoidea, rays, skate (fish), skates and sawfish) and Holocephali (chimaeras, sometimes called ghost sharks, which are sometimes separated into their own class). Extant chondrichthyans range in size from the finless sleeper ray to the over whale shark. Anatomy Skeleton The skeleton is cartilaginous. The notochord is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genome Duplications
Polyploidy is a condition in which the cells of an organism have more than two paired sets of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two complete sets of chromosomes, one from each of two parents; each set contains the same number of chromosomes, and the chromosomes are joined in pairs of homologous chromosomes. However, some organisms are polyploid. Polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally diploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis; the sporophyte generation is diploid and prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
