Role of epidermal cell turgor on stomatal regulation Lin isolated epidermal peelings of Citrullus colocynthis inn. (Schrad.)

1973 ◽  
Vol 164 (2) ◽  
pp. 180-187 ◽  
Author(s):  
M.C. Bhandari ◽  
David N. Sen
Keyword(s):  
Epidermal Cell ◽  
Citrullus Colocynthis ◽  
Stomatal Regulation ◽  
Cell Turgor

Role of actin in epidermal cell indirect adhesion.

1991 ◽  
Vol 53 (1) ◽  
pp. 3-6
Author(s):  
SHIN'ICHI INOHARA
Keyword(s):  
Epidermal Cell

scholarly journals Gab1 and SHP-2 promote Ras/MAPK regulation of epidermal growth and differentiation

2002 ◽  
Vol 159 (1) ◽  
pp. 103-112 ◽  
Author(s):  
Ti Cai ◽  
Keigo Nishida ◽  
Toshio Hirano ◽  
Paul A. Khavari
Keyword(s):  
Epidermal Cell ◽  
Mapk Signaling ◽  
Dominant Negative ◽  
Mapk Activity ◽  
Ras Activation ◽  
Proliferation And Differentiation ◽  
Epidermal Proliferation ◽  
Epidermal Growth ◽  
Docking Protein

În epidermis, Ras can influence proliferation and differentiation; however, regulators of epidermal Ras function are not fully characterized, and Ras effects on growth and differentiation are controversial. EGF induced Ras activation in epidermal cells along with phosphorylation of the multisubstrate docking protein Gab1 and its binding to SHP-2. Expression of mutant Gab1Y627F deficient in SHP-2 binding or dominant-negative SHP-2C459S reduced basal levels of active Ras and downstream MAPK proteins and initiated differentiation. Differentiation triggered by both Gab1Y627F and SHP-2C459S could be blocked by coexpression of active Ras, consistent with Gab1 and SHP-2 action upstream of Ras in this process. To study the role of Gab1 and SHP-2 in tissue, we generated human epidermis overexpressing active Gab1 and SHP-2. Both proteins stimulated proliferation. In contrast, Gab1Y627F and SHP-2C459S inhibited epidermal proliferation and enhanced differentiation. Consistent with a role for Gab1 and SHP-2 in sustaining epidermal Ras/MAPK activity, Gab1−/− murine epidermis displayed lower levels of active Ras and MAPK with postnatal Gab1−/− epidermis, demonstrating the hypoplasia and enhanced differentiation seen previously with transgenic epidermal Ras blockade. These data provide support for a Ras role in promoting epidermal proliferation and opposing differentiation and indicate that Gab1 and SHP-2 promote the undifferentiated epidermal cell state by facilitating Ras/MAPK signaling.

Fine structure of sensilla on the ovipositor of the tephritid fly Urophora affinis

1986 ◽  
Vol 64 (4) ◽  
pp. 973-984 ◽  
Author(s):  
R. Y. Zacharuk ◽  
R. M. K. W. Lee ◽  
D. E. Berube
Keyword(s):  
Fine Structure ◽  
Epidermal Cell ◽  
Fruit Flies ◽  
Sheath Cell ◽  
Outer Sheath ◽  
Dendritic Segment ◽  
Tubular Body ◽  
Tubular Bodies ◽  
Sheath Cells

There are four types of sensilla on the ovipositor blade of Urophora affinis Frauenfeld, one more than was observed on three other species of fruit flies studied by other authors. Three of the types, uniporous gustatory pegs, campaniform organs, and tactile short hairs are common to the four species and generally are in similar positions on the blade. The fourth, uniporous gustatory plates, were noted in U. affinis only. The chemosensilla are innervated by three chemosensory dendrites that terminate below the pore and a mechanosensory dendrite with a tubular body that is attached to a basal cuticular apodeme of the covering cuticle. The dendritic tubular bodies of the campaniform organs and tactile hairs terminate parallel to the surface in a right-angular bend, where they are attached to basal apodemes of the covering cuticle. The chemosensilla and tactile hairs have individual outer and inner sheath cells, but the campaniform organs have individual inner sheath cells only. The part of the ciliary dendritic segment that is encased by the dendritic sheath passes through an epidermal cell, often with several sensilla sharing the same epidermal cell in place of an outer sheath cell. The role of these sensilla during oviposition is discussed.

scholarly journals Variations in epidermal cell turgor of rust-infected barley seedlings

1991 ◽  
Vol 119 (4) ◽  
pp. 535-540 ◽  
Author(s):  
C. A. BERRYMAN ◽  
D. EAMUS ◽  
J. F. FARRAR
Keyword(s):  
Epidermal Cell ◽  
Cell Turgor

Role of xyloglucan breakdown in epidermal cell walls for auxininduced elongation of azuki bean epicotyl segments

1993 ◽  
Vol 87 (2) ◽  
pp. 142-147 ◽  
Author(s):  
Takayuki Hoson ◽  
Yoshiaki Sone ◽  
Akira Misaki ◽  
Yoshio Masuda
Keyword(s):  
Epidermal Cell ◽  
Cell Walls ◽  
Azuki Bean

Role of skin surface lipids in UV-induced epidermal cell changes

1991 ◽  
Vol 283 (3) ◽  
pp. 191-197 ◽  
Author(s):  
M. Picardo ◽  
C. Zompetta ◽  
C. De Luca ◽  
M. Cirone ◽  
A. Faggioni ◽  
...  
Keyword(s):  
Epidermal Cell ◽  
Skin Surface ◽  
Surface Lipids ◽  
Skin Surface Lipids ◽  
Cell Changes

Phloem water relations and root growth

2000 ◽  
Vol 27 (6) ◽  
pp. 539 ◽  
Author(s):  
Jeremy Pritchard ◽  
Sam Winch ◽  
Nick Gould
Keyword(s):  
Cell Expansion ◽  
Control Point ◽  
Turgor Pressure ◽  
Significant Proportion ◽  
Physiological Data ◽  
Solute Flux ◽  
Root Cells ◽  
Cell Turgor ◽  
The Relationship

In this paper the biophysical basis of cell expansion is described, paying particular attention to the waterrelations that underpin the process. The connection of growing root cells to the rest of the plant will be addressed and possible control points in the hardware identified. Examples of environmental modification of root extension, and therefore water and solute import, are given, and the relationship with current accepted theories of solute translocation discussed. The opportunities for delivery of solutes and water to be regulated by the growing root itself will be considered, in particular the dual role of cell wall loosening in decreasing both sink cell turgor and water potential. We conclude that a significant proportion of the water for cell expansion can enter growing root cells through the phloem. The physiological data presented rule out alterations in the turgor pressure difference between sieve element and cell as a modulator of solute flux. The plasmodesmata are identified as the major control point of solute flux along the symplastic pathway.

scholarly journals Supra-physiological levels of Gibberellins/DELLAs alter the patterning, morphology and abundance of root hairs in root tips of A. thaliana seedlings

2021 ◽  
Author(s):  
Iva McCarthy-Suarez
Keyword(s):  
Gene Expression ◽  
Cell Fate ◽  
Epidermal Cell ◽  
Root Hair ◽  
Root Hairs ◽  
Root Tip ◽  
Spatial Patterning ◽  
Root Tips ◽  
Root Epidermis

In spite of the known role of gibberellins (GAs), and of their antagonistic proteins, the DELLAs, in leaf hair production, no investigations, however, have assessed their hypothetical function in the production of root hairs. To this aim, the effects of supra-physiological levels of GAs/DELLAs on the spatial patterning of gene expression of the root hair (CPC) and root non-hair (GL2, EGL3 and WER) epidermal cell fate markers, as well as on the distribution, morphology and abundance of root hairs, were studied in root tips of 5-day-old A. thaliana seedlings. Results showed that excessive levels of GAs/DELLAs impaired the spatial patterning of gene expression of the root hair/non-hair epidermal cell fate markers, as well as the arrangement, shape and frequency of root hairs, giving rise to ectopic hairs and ectopic non-hairs, two-haired cells, two-tipped hairs, branched hairs, longer and denser hairs near the root tip under excessive DELLAs, and shorter and scarcer hairs near the root tip under excessive GAs. However, when the gai-1 (GA-insensitive-1) DELLA mutant protein was specifically over-expressed at the root epidermis, no changes in the patterning or abundance of root hairs occurred. Thus, these results suggest that, in seedlings of A. thaliana, the GAs/DELLAs might have a role in regulating the patterning, morphology and abundance of root hairs by acting from the sub-epidermal tissues of the root.

Sign in / Sign up

Export Citation Format

Share Document