Editing Microtubule (section)

==="Search and capture" model===

In 1986, [[Marc Kirschner]] and [[Tim Mitchison]] proposed that microtubules use their dynamic properties of growth and shrinkage at their plus ends to probe the three dimensional space of the cell. Plus ends that encounter kinetochores or sites of polarity become captured and no longer display growth or shrinkage. In contrast to normal dynamic microtubules, which have a half-life of 5–10 minutes, the captured microtubules can last for hours. This idea is commonly known as the "search and capture" model.<ref>{{Cite journal |vauthors=Kirschner M, Mitchison T |date=May 1986 |title=Beyond self-assembly: from microtubules to morphogenesis |journal=Cell |volume=45 |issue=3 |pages=329–42 |doi=10.1016/0092-8674(86)90318-1 |pmid=3516413 |s2cid=36994346}}</ref> Indeed, work since then has largely validated this idea. At the kinetochore, a variety of complexes have been shown to capture microtubule (+)-ends.<ref name="pmid18097444">{{Cite journal |vauthors=Cheeseman IM, Desai A |date=January 2008 |title=Molecular architecture of the kinetochore-microtubule interface |journal=Nature Reviews. Molecular Cell Biology |volume=9 |issue=1 |pages=33–46 |doi=10.1038/nrm2310 |pmid=18097444 |s2cid=34121605}}</ref> Moreover, a (+)-end capping activity for interphase microtubules has also been described.<ref name="pmid11058078">{{Cite journal |vauthors=Infante AS, Stein MS, Zhai Y, Borisy GG, Gundersen GG |date=November 2000 |title=Detyrosinated (Glu) microtubules are stabilized by an ATP-sensitive plus-end cap |url=http://jcs.biologists.org/cgi/pmidlookup?view=long&pmid=11058078 |url-status=live |journal=Journal of Cell Science |volume=113 |issue=22 |pages=3907–19 |doi=10.1242/jcs.113.22.3907 |pmid=11058078 |archive-url=https://web.archive.org/web/20240221025058/https://journals.biologists.com/jcs/cgi/pmidlookup |archive-date=2024-02-21 |access-date=2014-06-23}}</ref> This later activity is mediated by [[formins]],<ref name="pmid11483957">{{Cite journal |vauthors=Palazzo AF, Cook TA, Alberts AS, Gundersen GG |date=August 2001 |title=mDia mediates Rho-regulated formation and orientation of stable microtubules |journal=Nature Cell Biology |volume=3 |issue=8 |pages=723–9 |doi=10.1038/35087035 |pmid=11483957 |s2cid=7374170}}</ref> the [[adenomatous polyposis coli]] protein, and [[MAPRE1|EB1]],<ref name="pmid15311282">{{Cite journal |vauthors=Wen Y, Eng CH, Schmoranzer J, Cabrera-Poch N, Morris EJ, Chen M, Wallar BJ, Alberts AS, Gundersen GG |date=September 2004 |title=EB1 and APC bind to mDia to stabilize microtubules downstream of Rho and promote cell migration |journal=Nature Cell Biology |volume=6 |issue=9 |pages=820–30 |doi=10.1038/ncb1160 |pmid=15311282 |s2cid=29214110}}</ref> a protein that tracks along the growing plus ends of microtubules.