TY - JOUR
T1 - A functional link between localized Oskar, dynamic microtubules, and endocytosis
AU - Sanghavi, Paulomi
AU - Lu, Sumin
AU - Gonsalvez, Graydon Bennett
PY - 2012/7/1
Y1 - 2012/7/1
N2 - Many cell types including developing oocytes, fibroblasts, epithelia and neurons use mRNA localization as a means to establish polarity. The Drosophila oocyte has served as a useful model in dissecting the mechanism of mRNA localization. The polarity of the oocyte is established by the specific localization of three critical mRNAs-oskar, bicoid and gurken. The localization of these mRNAs requires microtubule integrity, and the activity of microtubule motors. However, the precise organization of the oocyte microtubule cytoskeleton remains an open question. In order to examine the polarity of oocyte microtubules, we visualized the localization of canonical microtubule plus end binding proteins, EB1 and CLIP-190. Both proteins were enriched at the posterior of the oocyte, with additional foci detected within the oocyte cytoplasm and along the cortex. Surprisingly, however, we found that this asymmetric distribution of EB1 and CLIP-190 was not essential for oskar mRNA localization. However, Oskar protein was required for recruiting the plus end binding proteins to the oocyte posterior. Lastly, our results suggest that the enrichment of growing microtubules at the posterior pole functions to promote high levels of endocytosis in this region of the cell. Thus, multiple polarity-determining pathways are functionally linked in the Drosophila oocytes.
AB - Many cell types including developing oocytes, fibroblasts, epithelia and neurons use mRNA localization as a means to establish polarity. The Drosophila oocyte has served as a useful model in dissecting the mechanism of mRNA localization. The polarity of the oocyte is established by the specific localization of three critical mRNAs-oskar, bicoid and gurken. The localization of these mRNAs requires microtubule integrity, and the activity of microtubule motors. However, the precise organization of the oocyte microtubule cytoskeleton remains an open question. In order to examine the polarity of oocyte microtubules, we visualized the localization of canonical microtubule plus end binding proteins, EB1 and CLIP-190. Both proteins were enriched at the posterior of the oocyte, with additional foci detected within the oocyte cytoplasm and along the cortex. Surprisingly, however, we found that this asymmetric distribution of EB1 and CLIP-190 was not essential for oskar mRNA localization. However, Oskar protein was required for recruiting the plus end binding proteins to the oocyte posterior. Lastly, our results suggest that the enrichment of growing microtubules at the posterior pole functions to promote high levels of endocytosis in this region of the cell. Thus, multiple polarity-determining pathways are functionally linked in the Drosophila oocytes.
KW - Actin anchoring
KW - Cell polarity
KW - Kinesin
KW - RNA localization
UR - http://www.scopus.com/inward/record.url?scp=84861706622&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84861706622&partnerID=8YFLogxK
U2 - 10.1016/j.ydbio.2012.04.024
DO - 10.1016/j.ydbio.2012.04.024
M3 - Article
C2 - 22561189
AN - SCOPUS:84861706622
SN - 0012-1606
VL - 367
SP - 66
EP - 77
JO - Developmental Biology
JF - Developmental Biology
IS - 1
ER -