» Articles » PMID: 25406088

The Role of Water Channel Proteins in Facilitating Recovery of Leaf Hydraulic Conductance from Water Stress in Populus Trichocarpa

Overview
Journal PLoS One
Date 2014 Nov 19
PMID 25406088
Citations 16
Authors
Affiliations
Soon will be listed here.
Abstract

Gas exchange is constrained by the whole-plant hydraulic conductance (Kplant). Leaves account for an important fraction of Kplant and may therefore represent a major determinant of plant productivity. Leaf hydraulic conductance (Kleaf) decreases with increasing water stress, which is due to xylem embolism in leaf veins and/or the properties of the extra-xylary pathway. Water flow through living tissues is facilitated and regulated by water channel proteins called aquaporins (AQPs). Here we assessed changes in the hydraulic conductance of Populus trichocarpa leaves during a dehydration-rewatering episode. While leaves were highly sensitive to drought, Kleaf recovered only 2 hours after plants were rewatered. Recovery of Kleaf was absent when excised leaves were bench-dried and subsequently xylem-perfused with a solution containing AQP inhibitors. We examined the expression patterns of 12 highly expressed AQP genes during a dehydration-rehydration episode to identify isoforms that may be involved in leaf hydraulic adjustments. Among the AQPs tested, several genes encoding tonoplast intrinsic proteins (TIPs) showed large increases in expression in rehydrated leaves, suggesting that TIPs contribute to reversing drought-induced reductions in Kleaf. TIPs were localized in xylem parenchyma, consistent with a role in facilitating water exchange between xylem vessels and adjacent living cells. Dye uptake experiments suggested that reversible embolism formation in minor leaf veins contributed to the observed changes in Kleaf.

Citing Articles

Responses to Drought Stress in Poplar: What Do We Know and What Can We Learn?.

Rosso L, Cantamessa S, Bergante S, Biselli C, Fricano A, Chiarabaglio P Life (Basel). 2023; 13(2).

PMID: 36836891 PMC: 9962866. DOI: 10.3390/life13020533.


Foliar water uptake as a source of hydrogen and oxygen in plant biomass.

Kagawa A Tree Physiol. 2022; 42(11):2153-2173.

PMID: 35554604 PMC: 9652008. DOI: 10.1093/treephys/tpac055.


Defoliation-induced compensatory transpiration is compromised in -RNAi .

Harding S, Frost C, Tsai C Plant Direct. 2020; 4(9):e00268.

PMID: 33015535 PMC: 7522500. DOI: 10.1002/pld3.268.


Stomatal Sensitivity to Vapor Pressure Deficit and the Loss of Hydraulic Conductivity Are Coordinated in , a Desert Phreatophyte Species.

Fan D, Dang Q, Xu C, Jiang C, Zhang W, Xu X Front Plant Sci. 2020; 11:1248.

PMID: 32922423 PMC: 7456922. DOI: 10.3389/fpls.2020.01248.


Combined high leaf hydraulic safety and efficiency provides drought tolerance in Caragana species adapted to low mean annual precipitation.

Yao G, Nie Z, Turner N, Li F, Gao T, Fang X New Phytol. 2020; 229(1):230-244.

PMID: 32749703 PMC: 7754512. DOI: 10.1111/nph.16845.


References
1.
Wilkins O, Nahal H, Foong J, Provart N, Campbell M . Expansion and diversification of the Populus R2R3-MYB family of transcription factors. Plant Physiol. 2008; 149(2):981-93. PMC: 2633813. DOI: 10.1104/pp.108.132795. View

2.
BARRIEU , CHAUMONT , Chrispeels . High expression of the tonoplast aquaporin ZmTIP1 in epidermal and conducting tissues of maize . Plant Physiol. 1998; 117(4):1153-63. PMC: 34879. DOI: 10.1104/pp.117.4.1153. View

3.
Tyree M, Sperry J . Do woody plants operate near the point of catastrophic xylem dysfunction caused by dynamic water stress? : answers from a model. Plant Physiol. 1988; 88(3):574-80. PMC: 1055627. DOI: 10.1104/pp.88.3.574. View

4.
Shatil-Cohen A, Attia Z, Moshelion M . Bundle-sheath cell regulation of xylem-mesophyll water transport via aquaporins under drought stress: a target of xylem-borne ABA?. Plant J. 2011; 67(1):72-80. DOI: 10.1111/j.1365-313X.2011.04576.x. View

5.
Guyot G, Scoffoni C, Sack L . Combined impacts of irradiance and dehydration on leaf hydraulic conductance: insights into vulnerability and stomatal control. Plant Cell Environ. 2011; 35(5):857-71. DOI: 10.1111/j.1365-3040.2011.02458.x. View