Participation of actin filaments, myosin and phosphatidylinositol 3-kinase in the formation and polarisation of tetraspore germ tube of Gelidium floridanum (Rhodophyta, Florideophyceae )

Plant Biology ◽  
2018 ◽  
Vol 21 (2) ◽  
pp. 352-360
Author(s):  
E. P. Filipin ◽  
D. T. Pereira ◽  
L. C. Ouriques ◽  
Z. L. Bouzon ◽  
C. Simioni
Keyword(s):  
Actin Filaments ◽  
Germ Tube ◽  
Phosphatidylinositol 3 Kinase ◽  
Gelidium Floridanum ◽  
Phosphatidylinositol 3

Disruption of Dictyostelium PI3K genes reduces [32P]phosphatidylinositol 3,4 bisphosphate and [32P]phosphatidylinositol trisphosphate levels, alters F-actin distribution and impairs pinocytosis

1998 ◽  
Vol 111 (2) ◽  
pp. 283-294 ◽  
Author(s):  
K. Zhou ◽  
S. Pandol ◽  
G. Bokoch ◽  
A.E. Traynor-Kaplan
Keyword(s):  
Cell Motility ◽  
Mutant Strain ◽  
Actin Filaments ◽  
Cell Structure ◽  
Structure And Function ◽  
Phosphatidylinositol 3 Kinase ◽  
And Function ◽  
Phosphatidylinositol 3

To understand how phosphatidylinositol 3-kinase (PI3K) modulates cell structure and function, we examined the molecular and cellular defects of a Dictyostelium mutant strain (pik1(Delta)2(Delta)) missing two (DdPIK1 and 2) of three PI3K genes, which are homologues of the mammalian p110 subunit. Levels of [32P]phosphatidylinositol 3, 4 bisphosphate (PI(3,4)P2) and [32P]phosphatidylinositol trisphosphate (PIP3) were reduced in pik1(Delta)2(Delta), which had major defects in morphological and functional correlates of macropinocytosis. This was accompanied by dramatic deficits in a subset of F-actin-enriched structures such as circular ruffles, actin crowns and pseudopodia. Although pik1(Delta)2(Delta) were mobile, they failed to aggregate into streams. Therefore we conclude that PIK1 and 2, possibly through modulation of the levels of PIP3 and PI(3,4)P2, regulate the organization of actin filaments necessary for circular ruffling during macropinocytosis, the extension of pseudopodia and the aggregation of cells into streams, but not the regulation of cell motility.

Possibility of distinct insulin-signaling pathways beyond phosphatidylinositol 3-kinase-mediating glucose transport and lipogenesis

Diabetes ◽  
1998 ◽  
Vol 47 (2) ◽  
pp. 179-185 ◽  
Author(s):  
R. W. Stevenson ◽  
D. K. Kreutter ◽  
K. M. Andrews ◽  
P. E. Genereux ◽  
E. M. Gibbs
Keyword(s):  
Signaling Pathways ◽  
Glucose Transport ◽  
Insulin Signaling ◽  
Phosphatidylinositol 3 Kinase ◽  
Phosphatidylinositol 3
Sign in / Sign up

Export Citation Format

Share Document