Epithelium and mesenchyme represent two extremes in the organization of groups of cells.
Epithelial cells array themselves into flat sheets or rolled tubes, while mesenchymal cells appear less coordinated in their structure-forming activities and form fewer and looser connections with other cells. These tissue-level differences are reflected at the level of the individual cell as well. Under the microscope, mesenchymal cells are amorphous and lack the distinct apical-basal polarity that characterizes their epithelial counterparts. Both types of cells contribute to the body's function in distinct ways, with epithelium being the essential structural and physiological component of organs and tissues such as the kidney and the lining of the gut, and mesenchyme forming all migratory cells, including metastatic cancer cells, as well providing support for the epithelium in various contexts. Despite (or perhaps because of) these differences, our anatomy contains countless examples of interaction between epithelial and mesenchymal cells. Indeed, nearly every one of the body's structures, from internal organs to limbs to teeth, is made up of a mesenchymal and an epithelial component.
Developmental biologists are particularly interested in the ability of each of these cell types to be converted into its counterpart, epithelial cells become mesenchymal, while in other situations the reverse transformation occurs. Now, Yoshiko Takahashi (Team Leader, RIKEN CDB Laboratory for Body Patterning; Kobe, Japan) and colleagues report a heretofore unknown mechanism by which mesenchymal-epithelial transitions (METs) are regulated in the embryogenesis of the chicken. The article, published in the September 14 issue of Developmental Cell, describes how a pair of intracellular molecules affects the ability of mesenchymal cells to convert into epithelial cells during the formation of somites early in embryogenesis. Somites are transitory structures that appear in a head-down directPage: 1 2 3 Related biology news :1
Contact: Doug Sipp
RIKEN Center for Developmental Biology
. There be dragons: New deep-sea predator species discovered2
. Woodpeckers: Theres a fungus among us3
. Theres no business like snow business4
. At Last Theres A Way To Fight The Dreaded E.coli5
. Researchers Find That Where Theres Muck Theres DNA Brass6
. "A Little Bit Here" And "A Little Bit There" Can Add Up To A Big Problem7
. Certain genes boost fish oils protection against breast cancer8
. New research suggests early diet may play key role in protecting against childhood leukaemia9
. $18 million bioinformatics center to become weapon against deadly diseases10
. Bodys own defense against H. pylori, cause of stomach ulcers and stomach cancer11
. Molecular therapeutics advance fight against brain cancer