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Figure 9-2 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-24 Molecular Biology of the Cell (© Garland Science 2008)
Figure Q9-3 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-14 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-13 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-15 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-18 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-21 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-20 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-22 Molecular Biology of the Cell (© Garland Science 2008)
Figure 9-17 Molecular Biology of the Cell (© Garland Science 2008)
Drugs can affect filament assembly
A PAR-1–dependent orientation gradient of dynamic microtubules directs posterior cargo transport in the
Drosophila oocyte
Richard M. Parton, Russell S. Hamilton, Graeme Ball, Lei Yang, C. Fiona Cullen, Weiping Lu, Hiroyuki Ohkura, and Ilan Davis
JCB Volume 194(1):121-135
July 11, 2011
© 2011 Parton et al.
A dynamic network of MTs extends throughout the oocyte posterior.
Parton R et al. JCB 2011;194:121-135
© 2011 Parton et al.
EB1 tracks the plus ends of dynamic MTs throughout the oocyte.
Parton R et al. JCB 2011;194:121-135
© 2011 Parton et al.
Staufen protein is transported on MTs at the oocyte posterior.
Parton R et al. JCB 2011;194:121-135
© 2011 Parton et al.
Analysis of EB1 trajectories reveals a graded bias in MT orientation.
Parton R et al. JCB 2011;194:121-135
© 2011 Parton et al.
MT nucleation occurs at discrete foci along the cortex but is absent from the posterior.
Parton R et al. JCB 2011;194:121-135
© 2011 Parton et al.
MTs are nucleated around the entire posterior in par-1 hypomorphic mutant oocytes, abolishing the orientation bias.
Parton R et al. JCB 2011;194:121-135
© 2011 Parton et al.
A biased random organization of MTs in the oocyte delivers cargoes to the posterior.
Parton R et al. JCB 2011;194:121-135
© 2011 Parton et al.
Figure 7-5 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-92 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-94 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-95 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-96 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-97 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-98 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-106 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-110 Molecular Biology of the Cell (© Garland Science 2008)
Figure 7-112 Molecular Biology of the Cell (© Garland Science 2008)
The Fate of mRNA Loaded With the miRISC
Targeted mRNA accumulates in P bodies
mRNA is stored in P bodies, undergoes degradation, or reenters the translation pathway
from Rana, Nature Rev.Mol.Cell Biol. 8, 23 (2007)
miRNAs Promote mRNA Deadenylation
from Huntzinger and Izaurralde, Nature Rev.Genet. 12, 99 (2011)
miRNA guide strand associates with AGO
AGO interacts with GW182
GW182 may compete with eIF4G for binding to PABPC and prevents mRNA circularization
Assembly of AGO-GW182-PABPC complex triggers deadenylation by CAF1-CCR4-NOT
GW182 may reduce the affinity of PABPC for the poly(A) tail
Fate of Deadenylated mRNAs
from Huntzinger and Izaurralde, Nature Rev.Genet. 12, 99 (2011)
Deadenylated mRNAs are stored in a translationally repressed state
Deadenylated mRNAs are decapped by DCP2 associated with decapping activators
Decapped mRNA is degraded by XRN1
Overview of RNA-Mediated Gene Silencing
from Eulalio et al., Nature Rev.Mol.Cell Biol. 8, 9 (2007)
siRNA triggers endonucleolytic cleavage of perfectly-matched complementary targets
The resulting mRNA fragments are degraded
miRNA triggers accelerated deadenylation and decapping of partially-complementary targets and requires Argonaute proteins and a P-body component
Cleavage is catalyzed by Argonaute proteins
miRNA represses translation
siRNA
miRNA
A MicroRNA Regulates Neuronal Differentiation by Controlling Alternative Splicing
miR-124 targets a component of a repressor of neuron-specific genes
miR-124 results in reduced expression of PTBP1 leading to the accumulation of PTBP2
PTBP2 results in a global switch to neuron- specific alternative splicing patterns
from Makeyev et al., Mol.Cell 27, 435 (2007)