Intraflagellar transport or IFT is a bidirectional motility along axonemal microtubules that is essential for the formation (ciliogenesis) and maintenance of most eukaryotic cilia and flagella. It is thought to be required to build all cilia that assemble within a membrane projection from the cell surface. Plasmodium falciparum cilia and the sperm flagella of Drosophila are examples of cilia that assemble in the cytoplasm and do not require IFT. The process of IFT involves movement of large protein complexes called IFT particles or trains from the cell body to the ciliary tip and followed by their return to the cell body. The outward or anterograde movement is powered by kinesin-2 while the inward or retrograde movement is powered by cytoplasmic dynein 2/1b. The IFT particles are composed of about 20 proteins organized in two subcomplexes called complex A and B.
IFT was first reported in 1993 by graduate student Keith Kozminski while working in the lab of Dr. Joel Rosenbaum at Yale University. The process of IFT has been best characterized in the biflagellate alga Chlamydomonas reinhardtii as well as the sensory cilia of the nematode Caenorhabditis elegans.
It has been suggested based on localization studies that IFT proteins also function outside of cilia.
Read more about Intraflagellar Transport: Biochemistry, Physiological Importance
Famous quotes containing the word transport:
“One may disavow and disclaim vices that surprise us, and whereto our passions transport us; but those which by long habits are rooted in a strong and ... powerful will are not subject to contradiction. Repentance is but a denying of our will, and an opposition of our fantasies.”
—Michel de Montaigne (1533–1592)