Coordinated expression of 3' hox genes during murine embryonal gut development: an enteric Hox code
J E Pitera1, V V Smith, P Thorogood
1Gastroenterology Unit, Institute of Child Health, University College London, London, England. J.Pitera@ich.ucl.ac.uk
Gastroenterology
|December 2, 1999
Summary
Hox genes 4 and 5 form a specific code in the developing gut. Their spatial and temporal expression patterns are crucial for correct enteric development and morphogenesis.
Area of Science:
- Developmental Biology
- Genetics
- Gastroenterology
Background:
- Hox genes are critical for morphogenesis and development.
- Their role in embryonic gut development is largely unknown.
- Hox paralogues 4 and 5 are expressed at key developmental sites.
Purpose of the Study:
- To investigate the spatial and temporal expression of Hox paralogues 4 and 5 in the developing mouse gut.
- To understand their potential role in enteric morphogenesis.
Main Methods:
- Studied CD1 mice embryos from embryonic days E8.5 to E17.5.
- Used in situ hybridization and immunohistochemistry to determine mRNA expression patterns.
- Analyzed expression in whole embryos, gastrointestinal tracts, and tissue sections.
Main Results:
- Observed distinct spatial, temporal, and combinatorial expression patterns across gut regions (foregut, prececal, cecum, postcecal).
- Identified coordinated rostral and caudal gradients with nested expression domains.
- Found region-specific expression domains in the stomach and cecum.
Conclusions:
- Expression patterns of Hox paralogues 4 and 5 suggest a specific enteric Hox code.
- This code is essential for correct enteric development and morphogenesis.
More Related Videos
Related Concept Videos
01:33Pleiotropy
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
01:56Gastrulation
Gastrulation establishes the three primary tissues of an embryo: the ectoderm, mesoderm, and endoderm. This developmental process relies on a series of intricate cellular movements, which in humans transforms a flat, “bilaminar disc” composed of two cell sheets into a three-tiered structure. In the resulting embryo, the endoderm serves as the bottom layer, and stacked directly above it is the intermediate mesoderm, and then the uppermost ectoderm. Respectively, these tissue strata will form...
01:30Neurulation
Neurulation is the embryological process which forms the precursors of the central nervous system and occurs after gastrulation has established the three primary cell layers of the embryo: ectoderm, mesoderm, and endoderm. In humans, the majority of this system is formed via primary neurulation, in which the central portion of the ectoderm—originally appearing as a flat sheet of cells—folds upwards and inwards, sealing off to form a hollow neural tube. As development proceeds, the anterior...
02:33Hedgehog Signaling Pathway
The Hedgehog gene (Hh) was first discovered due to its control of the growth of disorganized, hair-like bristles phenotype in Drosophila, much like hedgehog spines. Hh plays a crucial role in the development of organs and the maintenance of homeostasis in both invertebrates and vertebrates. However, while Drosophila has only one Hh protein, mammals have multiple functional Hedgehog proteins - Sonic (Shh), Desert (Dhh), and Indian Hedgehog (Ihh). All of these homologous proteins have adapted to...
01:20Embryonic Connective Tissues
During early development, the embryo forms two types of connective tissues— the mesenchyme and mucoid connective tissue.
The mesenchyme is the first connective tissue that emerges in the developing embryo. It consists of loosely arranged multipotent mesenchymal cells and reticular fibers in the extracellular matrix. This loose arrangement allows easy migration of cells, which is essential for germ layer positioning, patterning, and organ morphogenesis during embryonic development. Mesenchyme is...
The mesenchyme is the first connective tissue that emerges in the developing embryo. It consists of loosely arranged multipotent mesenchymal cells and reticular fibers in the extracellular matrix. This loose arrangement allows easy migration of cells, which is essential for germ layer positioning, patterning, and organ morphogenesis during embryonic development. Mesenchyme is...
01:15Development of the Sexual Organs in the Embryo and Fetus
Development of the reproductive organs in an embryo starts from a bipotential state. This means the early embryo can develop either male or female reproductive organs. The formation of these organs begins with the growth of gonadal ridges that arise from the intermediate mesoderm during the fifth week of development.
Near the gonadal ridges, two duct systems are present: the mesonephric ducts (Wolffian ducts) and paramesonephric ducts (Müllerian ducts). These ducts form the basis for the male...
Near the gonadal ridges, two duct systems are present: the mesonephric ducts (Wolffian ducts) and paramesonephric ducts (Müllerian ducts). These ducts form the basis for the male...