201
|
Nguyen MX, Moon S, Jung KH. Genome-wide expression analysis of rice aquaporin genes and development of a functional gene network mediated by aquaporin expression in roots. PLANTA 2013; 238:669-81. [PMID: 23801298 DOI: 10.1007/s00425-013-1918-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 06/10/2013] [Indexed: 05/21/2023]
Abstract
The world population continually faces challenges of water scarcity for agriculture. A common strategy called water-balance control has evolved to adapt plant growth to these challenges. Aquaporins are a family of integral membrane proteins that play a central role in water-balance control. In this study, we identified 34 members of the rice aquaporin gene family, adding a novel member to the previous list. A combination of phylogenetic tree and anatomical meta-expression profiling data consisting of 983 Affymetrix arrays and 209 Agilent 44 K arrays was used to identify tissue-preferred aquaporin genes and evaluate functional redundancy among aquaporin family members. Eight aquaporins showed root-preferred expression in the vegetative growth stage, while 4 showed leaf/shoot-preferred expression. Integrating stress-induced expression patterns into phylogenetic tree and semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) analyses revealed that 3 rice aquaporin genes were markedly downregulated and 4 were upregulated by water deficiency in the root, suggesting that these candidate genes are key regulators of water uptake from the soil. Finally, we constructed a functional network of genes mediated by water stress and refined the network by confirming the differential expression using RT-PCR and real-time PCR. Our data will be useful to elucidate the molecular mechanism of water-balance control in rice root.
Collapse
Affiliation(s)
- Minh Xuan Nguyen
- Department of Plant Molecular Systems Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin, 446-701, Korea
| | | | | |
Collapse
|
202
|
Navarro-Ródenas A, Bárzana G, Nicolás E, Carra A, Schubert A, Morte A. Expression analysis of aquaporins from desert truffle mycorrhizal symbiosis reveals a fine-tuned regulation under drought. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:1068-78. [PMID: 23656332 DOI: 10.1094/mpmi-07-12-0178-r] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We have performed the isolation, functional characterization, and expression analysis of aquaporins in roots and leaves of Helianthemum almeriense, in order to evaluate their roles in tolerance to water deficit. Five cDNAs, named HaPIP1;1, HaPIP1;2, HaPIP2;1, HaPIP2;2, and HaTIP1;1, were isolated from H. almeriense. A phylogenetic analysis of deduced proteins confirmed that they belong to the water channel proteins family. The HaPIP1;1, HaPIP2;1, and HaTIP1;1 genes encode functional water channel proteins, as indicated by expression assays in Saccharomyces cerevisiae, showing divergent roles in the transport of water, CO2, and NH3. The expression patterns of the genes isolated from H. almeriense and of a previously described gene from Terfezia claveryi (TcAQP1) were analyzed in mycorrhizal and nonmycorrhizal plants cultivated under well-watered or drought-stress conditions. Some of the studied aquaporins were subjected to fine-tuned expression only under drought-stress conditions. A beneficial effect on plant physiological parameters was observed in mycorrhizal plants with respect to nonmycorrhizal ones. Moreover, stress induced a change in the mycorrhizal type formed, which was more intracellular under drought stress. The combination of a high intracellular colonization, together with the fine-tuned expression of aquaporins could result in a morphophysiological adaptation of this symbiosis to drought conditions.
Collapse
Affiliation(s)
- Alfonso Navarro-Ródenas
- Departamento Biología Vegetal Botánica, Facultad de Biología, Universidad de Murcia, Murcia, Spain
| | | | | | | | | | | |
Collapse
|
203
|
Park KJ, Sa KJ, Koh HJ, Lee JK. QTL analysis for eating quality-related traits in an F2:3 population derived from waxy corn × sweet corn cross. BREEDING SCIENCE 2013; 63:325-332. [PMID: 24273428 PMCID: PMC3770560 DOI: 10.1270/jsbbs.63.325] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 07/15/2013] [Indexed: 06/02/2023]
Abstract
In order to identify quantitative trait loci (QTL) for the eating quality of waxy corn and sweet corn (Zea mays L.), QTL analysis was conducted on an F2 population derived from a cross between a waxy corn inbred line and a sweet corn inbred line. Ten QTLs for pericarp thickness (PER), amylose content (AMY), dextrose content (DEX) and sucrose content (SUC) were found in the 158 F2 families. Among them, four QTLs, qAMY4 (10.43%), qAMY9 (19.33%), qDEX4 (21.31%) and qSUC4 (30.71%), may be considered as major QTLs. Three of these, qAMY4, qDEX4 and qSUC4, were found to be located within a region flanked by two adjacent SSR markers on chromosome 4 (umc1088 and bnlg1265), making this SSR marker pair a useful selection tool for screening the eating quality traits of AMY, DEX and SUC. The QTL for amylose content was found to be located between markers phi027 and umc1634, raising the possibility of its identity being the Wx1 gene, which encodes a granule-bound amylose synthase. The new QTLs identified by the present study could serve as useful molecular markers for selecting important eating quality traits in subsequent waxy corn breeding studies.
Collapse
Affiliation(s)
- Ki Jin Park
- Maize Experiment Station, Kangwon Agricultural Research and Extension Services,
Hongcheon 250-823,
Korea
- Department of Plant Science, Plant Genomics and Breeding Institute, Seoul National University,
Seoul 151-921,
Korea
| | - Kyu Jin Sa
- Department of Applied Plant Sciences, College of Agriculture and Life Sciences, Kangwon National University,
Chuncheon 200-701,
Korea
| | - Hee-Jong Koh
- Department of Plant Science, Plant Genomics and Breeding Institute, Seoul National University,
Seoul 151-921,
Korea
| | - Ju Kyong Lee
- Department of Applied Plant Sciences, College of Agriculture and Life Sciences, Kangwon National University,
Chuncheon 200-701,
Korea
| |
Collapse
|
204
|
Lahiani MH, Dervishi E, Chen J, Nima Z, Gaume A, Biris AS, Khodakovskaya MV. Impact of carbon nanotube exposure to seeds of valuable crops. ACS APPLIED MATERIALS & INTERFACES 2013; 5:7965-73. [PMID: 23834323 DOI: 10.1021/am402052x] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Multiwalled carbon nanotubes (MWCNTs) affected seed germination, growth, and the development of three important crops (barley, soybean, corn). Early seed germination and activation of growth in exposed seedlings was observed when MWCNTs were added to sterile agar medium. Similarly, seed germination was activated for all tested crop species when MWCNTs were deposited on seed surfaces. The ability of MWCNTs to penetrate the seed coats of corn, barley, and soybean was proven by detection of nanotube agglomerates inside MWCNT-exposed seeds using Raman spectroscopy and transmission electron microscopy (TEM). Reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that the expression of genes encoding several types of water channel proteins was increased in soybean, corn, and barley seeds coated with MWCNTs compared with uncoated control seeds. Our results indicate that the positive effect of MWCNTs on the germination and growth of seedlings is reproducible between crop species and can be observed for different methods of delivering carbon nanotubes. Such studies could prove the significant potential of carbon nanotubes as regulators of germination and plant growth.
Collapse
Affiliation(s)
- Mohamed H Lahiani
- Department of Applied Science, University of Arkansas at Little Rock, Little Rock, Arkansas 72204, USA
| | | | | | | | | | | | | |
Collapse
|
205
|
Li DD, Ruan XM, Zhang J, Wu YJ, Wang XL, Li XB. Cotton plasma membrane intrinsic protein 2s (PIP2s) selectively interact to regulate their water channel activities and are required for fibre development. THE NEW PHYTOLOGIST 2013; 199:695-707. [PMID: 23656428 DOI: 10.1111/nph.12309] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 04/03/2013] [Indexed: 05/10/2023]
Abstract
Aquaporins are thought to be associated with water transport and play important roles in cotton (Gossypium hirsutum) fibre elongation. Among aquaporins, plasma membrane intrinsic proteins (PIPs) constitute a plasma-membrane-specific subfamily and are further subdivided into PIP1 and PIP2 groups. In this study, four fibre-preferential GhPIP2 genes were functionally characterized. The selective interactions among GhPIP2s and their interaction proteins were studied in detail to elucidate the molecular mechanism of cotton fibre development. GhPIP2;3 interacted with GhPIP2;4 and GhPIP2;6, but GhPIP2;6 did not interact with GhPIP2;4. Coexpression of GhPIP2;3/2;4 or GhPIP2;3/2;6 resulted in a positive cooperative effect which increased the permeability coefficient of oocytes, while GhPIP2;4/2;6 did not. GhBCP2 (a blue copper-binding protein) inhibited GhPIP2;6 water channel activity through their interaction. Overexpression of GhPIP2 genes in yeast induced longitudinal growth of the host cells. By contrast, knockdown of expression of GhPIP2 genes in cotton by RNA interference markedly hindered fibre elongation. In conclusion, GhPIP2 proteins are the primary aquaporin isoforms in fibres. They selectively form hetero-oligomers in order to regulate their activities to meet the requirements for rapid fibre elongation.
Collapse
Affiliation(s)
- Deng-Di Li
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Central China Normal University, Wuhan, China
| | | | | | | | | | | |
Collapse
|
206
|
Lawrence SD, Novak NG, Xu H, Cooke JE. Herbivory of maize by southern corn rootworm induces expression of the major intrinsic protein ZmNIP1;1 and leads to the discovery of a novel aquaporin ZmPIP2;8. PLANT SIGNALING & BEHAVIOR 2013; 8:e24937. [PMID: 23673351 PMCID: PMC3999062 DOI: 10.4161/psb.24937] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Revised: 05/03/2013] [Accepted: 05/04/2013] [Indexed: 05/03/2023]
Abstract
Aquaporins channel water and other neutral molecules through cell membranes. Aquaporin gene expression is subject to transcriptional control and can be modulated by factors affecting water balance such as salt, abscisic acid and drought. During infestation of maize by southern corn rootworm (SCR), an insect that chews into and significantly damages maize roots, three maize aquaporins were differentially expressed upon prolonged infestation. Using a brief infestation of maize roots ZmNIP1;1 transcript abundance again increased under infestation while expression of a new aquaporin, ZmPIP2;8 and ZmTIP2;2 expression did not change. Since ZmPIP2;8 has not been described previously, the deduced protein sequence was analyzed in silico and found to contain the hallmarks of plant aquaporins, with a predicted protein structure similar to other functionally characterized PIP2s. NIPs characterized to date have been implicated in facilitating the movement of a variety of small molecules, while TIPs and PIPs often have the capacity to facilitate trans-membrane movement of water. Functional assays (using heterologous expression in Xenopus laevis oocytes) of ZmTIP2;2 and ZmPIP2;8 confirmed that these aquaporins demonstrate water channel capacity.
Collapse
Affiliation(s)
- Susan D. Lawrence
- USDA-ARS; Invasive Insect Biocontrol and Behavior Lab; BARC-West; Beltsville, MD USA
| | - Nicole G. Novak
- USDA-ARS; Invasive Insect Biocontrol and Behavior Lab; BARC-West; Beltsville, MD USA
| | - Hao Xu
- Department of Biological Sciences; University of Alberta; Edmonton, AB Canada
| | - Janice E.K. Cooke
- Department of Biological Sciences; University of Alberta; Edmonton, AB Canada
| |
Collapse
|
207
|
Azad AK, Hanawa R, Ishikawa T, Sawa Y, Shibata H. Expression profiles of aquaporin homologues and petal movement during petal development in Tulipa gesneriana. PHYSIOLOGIA PLANTARUM 2013; 148:397-407. [PMID: 23088645 DOI: 10.1111/j.1399-3054.2012.01717.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Indexed: 06/01/2023]
Abstract
Previously, we have characterized two tonoplast intrinsic proteins (TIPs) and four plasma membrane intrinsic proteins (PIPs) from the 2-day-old petals of tulip (Tulipa gesneriana). In this study, we analyzed the development of tulip petals and stems, temperature-dependent petal movement, the amount of ³H₂O transported into petals and stems during petal movement, and the transcript levels of two TIP (TgTIP1;1 and TgTIP1;2) and four TgPIP genes in petals and stems, from the first day of petal opening to day 12. The development of the petals and stems was completed by days 6 and 9, respectively, after the first day of petal opening. Temperature-dependent petal movement and the amount of ³H₂O that was transported into petals could be detected at significant levels up to day 6 with petal movement reaching a peak at day 3. Real-time reverse transcription-polymerase chain reaction analysis revealed that TgTIP1;1 and TgTIP1;2 were expressed ubiquitously in petals, stems, leaves, bulbs and roots. However, the expression level of TgTIP1;2 was very low in bulbs. The expression of both TgTIP1 genes was upregulated in close association with the development of petals but not with that of the stem. The four TgPIP genes were expressed at almost the same level during the development of the petals and the stem. However, the levels of the TgTIP1 and TgPIP transcripts in petals decreased during the course of petal wilting from day 9 onwards. These results suggest that TgTIP1;1 and TgTIP1;2 may contribute to petal development.
Collapse
Affiliation(s)
- Abul Kalam Azad
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan.
| | | | | | | | | |
Collapse
|
208
|
Aslam U, Khatoon A, Cheema HMN, Bashir A. Identification and characterization of plasma membrane aquaporins isolated from fiber cells of Calotropis procera. J Zhejiang Univ Sci B 2013; 14:586-95. [PMID: 23825144 PMCID: PMC3709063 DOI: 10.1631/jzus.b1200233] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 05/03/2013] [Indexed: 11/11/2022]
Abstract
Calotropis procera, commonly known as "milkweed", possesses long seed trichomes for seed dispersal and has the ability to survive under harsh conditions such as drought and salinity. Aquaporins are water channel proteins expressed in all land plants, divided into five subfamilies plasma membrane intrinsic proteins (PIPs), tonoplast intrinsic proteins (TIPs), NOD26-like proteins (NIPs), small basic intrinsic proteins (SIPs), and the unfamiliar X intrinsic proteins (XIPs). PIPs constitute the largest group of water channel proteins that are involved in different developmental and regulatory mechanisms including water permeability, cell elongation, and stomata opening. Aquaporins are also involved in abiotic stress tolerance and cell expansion mechanisms, but their role in seed trichomes (fiber cells) has never been investigated. A large number of clones isolated from C. procera fiber cDNA library showed sequence homology to PIPs. Both expressed sequence tags (ESTs) and real-time polymerase chain reaction (PCR) studies revealed that the transcript abundance of this gene family in fiber cells of C. procera is greater than that of cotton. Full-length cDNAs of CpPIP1 and CpPIP2 were isolated from C. procera fiber cDNA library and used for constructing plant expression vectors under constitutive (2×35S) and trichome-specific (GhLTP3) promoters. Transgenic tobacco plants were developed via Agrobacterium-mediated transformation. The phenotypic characteristics of the plants were observed after confirming the integration of transgene in plants. It was observed that CpPIP2 expression cassette under 2×35S and GhLTP3 promoter enhanced the numbers of stem and leave trichomes. However, 2×35S::CpPIP2 has a more amplified effect on trichome density and length than GhLTP3::CpPIP2 and other PIP constructs. These findings imply the role of C. procera PIP aquaporins in fiber cell elongation. The PIPs-derived cell expansion mechanism may be exploited through transgenic approaches for improvement of fiber staple length in cotton and boosting of defense against sucking insects by enhancing plant pubescence.
Collapse
Affiliation(s)
- Usman Aslam
- National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road, Faisalabad 38000, Pakistan.
| | | | | | | |
Collapse
|
209
|
Murozuka E, Hanisch S, Pomorski TG, Jahn TP, Schjoerring JK. Bimolecular fluorescence complementation and interaction of various Arabidopsis major intrinsic proteins expressed in yeast. PHYSIOLOGIA PLANTARUM 2013; 148:422-31. [PMID: 23163742 DOI: 10.1111/ppl.12000] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 10/11/2012] [Accepted: 10/12/2012] [Indexed: 05/11/2023]
Abstract
Tonoplast intrinsic proteins (TIPs) and plasma membrane intrinsic proteins (PIPs) form subgroups of plant major intrinsic proteins (MIPs) that channel water as well as various small neutral molecules across the tonoplast and plasma membrane. Most MIPs are believed to form homotetramers, while some plant PIPs have been shown to form heterotetramers composed of different isoforms. This study investigated in vivo molecular interactions between different Arabidopsis TIP isoforms and between TIPs and a PIP member. The interactions were assayed by bimolecular fluorescence complementation optimized for use in Saccharomyces cerevisiae as a heterologous expression system. Fluorescence of re-assembled Venus yellow fluorescent protein was monitored by fluorescence microscopy and flow cytometry. The results showed strong interactions between TIP1;2, TIP2;1 and TIP3;1. Surprisingly, the three TIP isoforms also interacted with PIP2;1. The potassium channel AKT1 was used as a negative control and exhibited no interaction with any of the MIPs. The observed interactions may play a role in targeting and regulation of MIPs in plants.
Collapse
Affiliation(s)
- Emiko Murozuka
- Department of Plant and Environmental Sciences, Plant and Soil Science Section, Faculty of Science, University of Copenhagen, Frederiksberg C, DK-1871, Denmark
| | | | | | | | | |
Collapse
|
210
|
Hachez C, Besserer A, Chevalier AS, Chaumont F. Insights into plant plasma membrane aquaporin trafficking. TRENDS IN PLANT SCIENCE 2013; 18:344-52. [PMID: 23291163 DOI: 10.1016/j.tplants.2012.12.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 11/30/2012] [Accepted: 12/05/2012] [Indexed: 05/11/2023]
Abstract
Plasma membrane intrinsic proteins (PIPs) are plant aquaporins that facilitate the diffusion of water and small uncharged solutes through the cell membrane. Deciphering the network of interacting proteins that modulate PIP trafficking to and activity in the plasma membrane is essential to improve our knowledge about PIP regulation and function. This review highlights the most recent advances related to PIP subcellular routing and dynamic redistribution, identifies some key molecular interacting proteins, and indicates exciting directions for future research in this field. A better understanding of the mechanisms by which plants optimize water movement might help in identifying new molecular players of agronomical relevance involved in the control of cellular water uptake and drought tolerance.
Collapse
Affiliation(s)
- Charles Hachez
- Institut des Sciences de la Vie, Université Catholique de Louvain, Croix du Sud 4-L7.07.14, B-1348 Louvain-la-Neuve, Belgium
| | | | | | | |
Collapse
|
211
|
Luu DT, Maurel C. Aquaporin Trafficking in Plant Cells: An Emerging Membrane-Protein Model. Traffic 2013; 14:629-35. [DOI: 10.1111/tra.12062] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/18/2013] [Accepted: 02/21/2013] [Indexed: 11/29/2022]
Affiliation(s)
| | - Christophe Maurel
- Biochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes; UMR 5004 CNRS/UMR 0386 INRA/Montpellier SupAgro/Université Montpellier 2; F-34060; Montpellier Cedex 2; France
| |
Collapse
|
212
|
Leng H, Lu M, Wan X. Variation in embolism occurrence and repair along the stem in drought-stressed and re-watered seedlings of a poplar clone. PHYSIOLOGIA PLANTARUM 2013; 147:329-339. [PMID: 22686493 DOI: 10.1111/j.1399-3054.2012.01665.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 05/13/2012] [Accepted: 05/28/2012] [Indexed: 05/28/2023]
Abstract
Root pressure and plasma membrane intrinsic protein (PIP) availability in the xylem have been recognized to participate in the refilling of embolized conduits, yet integration of the two mechanisms has not been reported in the same plant. In this study, 4-month-old seedlings of a hybrid poplar (Populus alba × Populus glandulosa) clone 84K were subjected to two contrasting soil-water treatments, with the drought treatment involving withholding of water for 17 days to reduce the soil-water content to 10% of the saturated field capacity, followed by a re-watering cycle. The percentage loss of stem hydraulic conductance (PLC) sharply increased, and stomatal conductance and photosynthesis declined in response to drought stress; these processes were gradually restored following the subsequent re-watering. Embolism was most severe in the middle portions of the stem, followed by the basal and top portions of the stems of seedlings subjected to drought stress and subsequent re-watering. Although drought stress eliminated root pressure, re-watering partially restored it in a short period of time. The expression of PIP genes in the xylem was activated by drought stress, and some PIP genes were further stimulated in the top portion after re-watering. The dynamics of root pressure and differential expression of PIP genes along the stem coincided with changes in PLC, suggesting that root pressure and PIPs work together to refill the embolized vessels. On the basis of the recovery dynamics in PLC and g(smax) (maximum stomatal conductance) after re-watering, the stomatal closure and xylem cavitation exhibited fatigue due to drought stress.
Collapse
Affiliation(s)
- Huani Leng
- State key lab of forest genetics and tree breeding, Chinese Academy of Forestry, Beijing, 100091, China
| | | | | |
Collapse
|
213
|
Zhang DY, Ali Z, Wang CB, Xu L, Yi JX, Xu ZL, Liu XQ, He XL, Huang YH, Khan IA, Trethowan RM, Ma HX. Genome-wide sequence characterization and expression analysis of major intrinsic proteins in soybean (Glycine max L.). PLoS One 2013; 8:e56312. [PMID: 23437113 PMCID: PMC3577755 DOI: 10.1371/journal.pone.0056312] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 01/08/2013] [Indexed: 01/24/2023] Open
Abstract
Water is essential for all living organisms. Aquaporin proteins are the major facilitator of water transport activity through cell membranes of plants including soybean. These proteins are diverse in plants and belong to a large major intrinsic (MIP) protein family. In higher plants, MIPs are classified into five subfamilies including plasma membrane intrinsic proteins (PIP), tonoplast intrinsic proteins (TIP), NOD26-like intrinsic proteins (NIP), small basic intrinsic proteins (SIP), and the recently discovered X intrinsic proteins (XIP). This paper reports genome wide assembly of soybean MIPs, their functional prediction and expression analysis. Using a bioinformatic homology search, 66 GmMIPs were identified in the soybean genome. Phylogenetic analysis of amino acid sequences of GmMIPs divided the large and highly similar multi-gene family into 5 subfamilies: GmPIPs, GmTIPs, GmNIPs, GmSIPs and GmXIPs. GmPIPs consisted of 22 genes and GmTIPs 23, which showed high sequence similarity within subfamilies. GmNIPs contained 13 and GmSIPs 6 members which were diverse. In addition, we also identified a two member GmXIP, a distinct 5(th) subfamily. GmMIPs were further classified into twelve subgroups based on substrate selectivity filter analysis. Expression analyses were performed for a selected set of GmMIPs using semi-quantitative reverse transcription (semi-RT-qPCR) and qPCR. Our results suggested that many GmMIPs have high sequence similarity but diverse roles as evidenced by analysis of sequences and their expression. It can be speculated that GmMIPs contains true aquaporins, glyceroporins, aquaglyceroporins and mixed transport facilitators.
Collapse
Affiliation(s)
- Da Yong Zhang
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Zulfiqar Ali
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan
| | - Chang Biao Wang
- Cotton Research Institute, Shanxi Agricultural Sciences, Yuncheng, China
| | - Ling Xu
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Jin Xin Yi
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Zhao Long Xu
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- Nanjing Agricultural University, Nanjing, China
| | - Xiao Qing Liu
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Xiao Lan He
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yi Hong Huang
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Iqrar Ahmad Khan
- College of Agriculture & Applied Biology, University of Agriculture, Faisalabad, Pakistan
| | | | - Hong Xiang Ma
- Institute of Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| |
Collapse
|
214
|
Liu C, Fukumoto T, Matsumoto T, Gena P, Frascaria D, Kaneko T, Katsuhara M, Zhong S, Sun X, Zhu Y, Iwasaki I, Ding X, Calamita G, Kitagawa Y. Aquaporin OsPIP1;1 promotes rice salt resistance and seed germination. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2013; 63:151-8. [PMID: 23262183 DOI: 10.1016/j.plaphy.2012.11.018] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 11/14/2012] [Indexed: 05/07/2023]
Abstract
OsPIP1;1 is one of the most abundant aquaporins in rice leaves and roots and is highly responsible to environmental stresses. However, its biochemical and physiological functions are still largely unknown. The oocyte assay data showed OsPIP1;1 had lower water channel activity in contrast to OsPIP2;1. EGFP and immunoelectron microscopy studies revealed OsPIP1;1 was predominantly localized in not only plasma membrane but also in some ER-like intracellular compartments in the cells. OsPIP1;1 exhibited low water channel activity in Xenopus oocytes but coexpression of OsPIP2;1 significantly enhanced its water permeability. Stop-flow assay indicated that 10His-OsPIP1;1-reconstituted proteoliposomes had significantly higher water permeability than the control liposomes. Overexpression of OsPIP1;1 greatly altered many physiological features of transgenic plants in a dosage-dependent manner. Moderate expression of OsPIP1;1 increased rice seed yield, salt resistance, root hydraulic conductivity, and seed germination rate. This work suggests OsPIP1;1 functions as an active water channel and plays important physiological roles.
Collapse
Affiliation(s)
- Chengwei Liu
- Graduate School of Bioresource Sciences, Akita Prefectural University, Shimoshinjo, Akita 010-0195, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
215
|
Zhang J, Li D, Zou D, Luo F, Wang X, Zheng Y, Li X. A cotton gene encoding a plasma membrane aquaporin is involved in seedling development and in response to drought stress. Acta Biochim Biophys Sin (Shanghai) 2013. [PMID: 23178915 DOI: 10.1093/abbs/gms096] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cotton (Gossypium hirsutum), the most important textile crop worldwide, often encounters abiotic stress such as drought and waterlog during its growth season (summer), and its productivity is significantly limited by adverse factors. To investigate the molecular adaptation mechanisms of this plant species to abiotic stress, a gene encoding the plasma membrane intrinsic protein (PIP) was isolated in cotton, and designated as GhPIP2;7. Quantitative reverse transcriptase polymerase chain reaction analysis indicated that GhPIP2;7 was preferentially expressed in cotyledons and leaves, and its expression was up-regulated in leaves after drought treatments. Strong expression of GUS gene driven by GhPIP2;7 promoter was detected in leaves of 5- to 10-day-old transgenic Arabidopsis seedlings, but GUS activity gradually became weak as the seedlings further developed. GhPIP2;7 promoter activity was also remarkably induced by mannitol treatment. Furthermore, yeast cells over-expressing GhPIP2;7 displayed relatively higher drought tolerance, compared with controls. Over-expression of GhPIP2;7 in Arabidopsis enhanced plant tolerance to drought stress. Collectively, these data suggested that GhPIP2;7 gene may be involved in leaf development and in response to drought stress.
Collapse
Affiliation(s)
- Jie Zhang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Central China Normal University, Wuhan 430079, China
| | | | | | | | | | | | | |
Collapse
|
216
|
Abstract
Thanks to advances in next-generation technologies, genome sequences are now being generated at breadth (e.g. across environments) and depth (thousands of closely related strains, individuals or samples) unimaginable only a few years ago. Phylogenomics--the study of evolutionary relationships based on comparative analysis of genome-scale data--has so far been developed as industrial-scale molecular phylogenetics, proceeding in the two classical steps: multiple alignment of homologous sequences, followed by inference of a tree (or multiple trees). However, the algorithms typically employed for these steps scale poorly with number of sequences, such that for an increasing number of problems, high-quality phylogenomic analysis is (or soon will be) computationally infeasible. Moreover, next-generation data are often incomplete and error-prone, and analysis may be further complicated by genome rearrangement, gene fusion and deletion, lateral genetic transfer, and transcript variation. Here we argue that next-generation data require next-generation phylogenomics, including so-called alignment-free approaches.
Collapse
Affiliation(s)
- Cheong Xin Chan
- Institute for Molecular Bioscience, and ARC Centre of Excellence in Bioinformatics, The University of Queensland, Brisbane, QLD, 4072, Australia
| | | |
Collapse
|
217
|
Zhou S, Hu W, Deng X, Ma Z, Chen L, Huang C, Wang C, Wang J, He Y, Yang G, He G. Overexpression of the wheat aquaporin gene, TaAQP7, enhances drought tolerance in transgenic tobacco. PLoS One 2012; 7:e52439. [PMID: 23285044 PMCID: PMC3527513 DOI: 10.1371/journal.pone.0052439] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 11/13/2012] [Indexed: 11/21/2022] Open
Abstract
Aquaporin (AQP) proteins have been shown to transport water and other small molecules through biological membranes, which is crucial for plants to combat stress caused by drought. However, the precise role of AQPs in drought stress response is not completely understood in plants. In this study, a PIP2 subgroup gene AQP, designated as TaAQP7, was cloned and characterized from wheat. Expression of TaAQP7-GFP fusion protein revealed its localization in the plasma membrane. TaAQP7 exhibited high water channel activity in Xenopus laevis oocytes and TaAQP7 transcript was induced by dehydration, and treatments with polyethylene glycol (PEG), abscisic acid (ABA) and H(2)O(2). Further, TaAQP7 was upregulated after PEG treatment and was blocked by inhibitors of ABA biosynthesis, implying that ABA signaling was involved in the upregulation of TaAQP7 after PEG treatment. Overexpression of TaAQP7 increased drought tolerance in tobacco. The transgenic tobacco lines had lower levels of malondialdehyde (MDA) and H(2)O(2), and less ion leakage (IL), but higher relative water content (RWC) and superoxide dismutase (SOD) and catalase (CAT) activities when compared with the wild type (WT) under drought stress. Taken together, our results show that TaAQP7 confers drought stress tolerance in transgenic tobacco by increasing the ability to retain water, reduce ROS accumulation and membrane damage, and enhance the activities of antioxidants.
Collapse
Affiliation(s)
- Shiyi Zhou
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Wei Hu
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Xiaomin Deng
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Zhanbing Ma
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Lihong Chen
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Chao Huang
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Chen Wang
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Jie Wang
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Yanzhen He
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Guangxiao Yang
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Guangyuan He
- Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China
| |
Collapse
|
218
|
Shibasaka M, Sasano S, Utsugi S, Katsuhara M. Functional characterization of a novel plasma membrane intrinsic protein2 in barley. PLANT SIGNALING & BEHAVIOR 2012; 7:1648-52. [PMID: 23073013 PMCID: PMC3578906 DOI: 10.4161/psb.22294] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Water homeostasis is crucial to the growth and survival of plants. Plasma membrane intrinsic proteins (PIPs) have been shown to be primary channels mediating water uptake in plant cells. We characterized a novel PIP2 gene, HvPIP2;8 in barley (Hordeum vulgare). HvPIP2;8 shared 72-76% identity with other HvPIP2s and 74% identity with rice OsPIP2;8. The gene was expressed in all organs including the shoots, roots and pistil at a similar level. When HvPIP2;8 was transiently expressed in onion epidermal cells, it was localized to the plasma membrane. HvPIP2;8 showed transport activity for water in Xenopus oocytes, however its interaction with HvPIP1;2 was not observed. These results suggest that HvPIP2;8 plays a role in water homeostasis although further functional analysis is required in future.
Collapse
Affiliation(s)
- Mineo Shibasaka
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan.
| | | | | | | |
Collapse
|
219
|
Hu W, Yuan Q, Wang Y, Cai R, Deng X, Wang J, Zhou S, Chen M, Chen L, Huang C, Ma Z, Yang G, He G. Overexpression of a wheat aquaporin gene, TaAQP8, enhances salt stress tolerance in transgenic tobacco. PLANT & CELL PHYSIOLOGY 2012; 53:2127-41. [PMID: 23161856 DOI: 10.1093/pcp/pcs154] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Aquaporin (AQP) proteins have been shown to transport water and other small molecules through biological membranes, which is crucial for plants to combat salt stress. However, the precise role of AQP genes in salt stress response is not completely understood in plants. In this study, a PIP1 subgroup AQP gene, designated TaAQP8, was cloned and characterized from wheat. Transient expression of TaAQP8-green fluorescent protein (GFP) fusion protein revealed its localization in the plasma membrane. TaAQP8 exhibited water channel activity in Xenopus laevis oocytes. TaAQP8 transcript was induced by NaCl, ethylene and H(2)O(2). Further investigation showed that up-regulation of TaAQP8 under salt stress involves ethylene and H(2)O(2) signaling, with ethylene causing a positive effect and H(2)O(2) acting as a negative factor. Overexpression of TaAQP8 in tobacco increased root elongation compared with controls under salt stress. The roots of transgenic plants also retained a high K(+)/Na(+) ratio and Ca(2+) content, but reduced H(2)O(2) accumulation by an enhancement of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities under salt stress. Further investigation showed that whole seedlings from transgenic lines displayed higher SOD, CAT and POD activities, increased NtSOD and NtCAT transcript levels, and decreased H(2)O(2) accumulation and membrane injury under salt stress. Taken together, our results demonstrate that TaAQP8 confers salt stress tolerance not only by retaining high a K(+)/Na(+) ratio and Ca(2+) content, but also by reducing H(2)O(2) accumulation and membrane damage by enhancing the antioxidant system.
Collapse
Affiliation(s)
- Wei Hu
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research Wuhan Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology, Wuhan 430074, PR China
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
220
|
|
221
|
Belarmino LC, da S Oliveira AR, Brasileiro-Vidal AC, de A Bortoleti KC, Bezerra-Neto JP, Abdelnoor RV, Benko-Iseppon AM. Mining plant genome browsers as a means for efficient connection of physical, genetic and cytogenetic mapping: An example using soybean. Genet Mol Biol 2012; 35:335-47. [PMID: 22802719 PMCID: PMC3392886 DOI: 10.1590/s1415-47572012000200015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Physical maps are important tools to uncover general chromosome structure as well as to compare different plant lineages and species, helping to elucidate genome structure, evolution and possibilities regarding synteny and colinearity. The increasing production of sequence data has opened an opportunity to link information from mapping studies to the underlying sequences. Genome browsers are invaluable platforms that provide access to these sequences, including tools for genome analysis, allowing the integration of multivariate information, and thus aiding to explain the emergence of complex genomes. The present work presents a tutorial regarding the use of genome browsers to develop targeted physical mapping, providing also a general overview and examples about the possibilities regarding the use of Fluorescent In Situ Hybridization (FISH) using bacterial artificial chromosomes (BAC), simple sequence repeats (SSR) and rDNA probes, highlighting the potential of such studies for map integration and comparative genetics. As a case study, the available genome of soybean was accessed to show how the physical and in silico distribution of such sequences may be compared at different levels. Such evaluations may also be complemented by the identification of sequences beyond the detection level of cytological methods, here using members of the aquaporin gene family as an example. The proposed approach highlights the complementation power of the combination of molecular cytogenetics and computational approaches for the anchoring of coding or repetitive sequences in plant genomes using available genome browsers, helping in the determination of sequence location, arrangement and number of repeats, and also filling gaps found in computational pseudochromosome assemblies.
Collapse
Affiliation(s)
- Luis C Belarmino
- Laboratório de Genética e Biotecnologia Vegetal, Departamento de Genética, Universidade Federal de Pernambuco, Recife, PE, Brazil
| | | | | | | | | | | | | |
Collapse
|
222
|
Soto G, Alleva K, Amodeo G, Muschietti J, Ayub ND. New insight into the evolution of aquaporins from flowering plants and vertebrates: Orthologous identification and functional transfer is possible. Gene 2012; 503:165-76. [DOI: 10.1016/j.gene.2012.04.021] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Accepted: 04/09/2012] [Indexed: 12/18/2022]
|
223
|
A conserved cysteine residue is involved in disulfide bond formation between plant plasma membrane aquaporin monomers. Biochem J 2012; 445:101-11. [DOI: 10.1042/bj20111704] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
AQPs (aquaporins) are conserved in all kingdoms of life and facilitate the rapid diffusion of water and/or other small solutes across cell membranes. Among the different plant AQPs, PIPs (plasma membrane intrinsic proteins), which fall into two phylogenetic groups, PIP1 and PIP2, play key roles in plant water transport processes. PIPs form tetramers in which each monomer acts as a functional channel. The intermolecular interactions that stabilize PIP oligomer complexes and are responsible for the resistance of PIP dimers to denaturating conditions are not well characterized. In the present study, we identified a highly conserved cysteine residue in loop A of PIP1 and PIP2 proteins and demonstrated by mutagenesis that it is involved in the formation of a disulfide bond between two monomers. Although this cysteine seems not to be involved in regulation of trafficking to the plasma membrane, activity, substrate selectivity or oxidative gating of ZmPIP1s (Zm is Zea mays), ZmPIP2s and hetero-oligomers, it increases oligomer stability under denaturating conditions. In addition, when PIP1 and PIP2 are co-expressed, the loop A cysteine of ZmPIP1;2, but not that of ZmPIP2;5, is involved in the mercury sensitivity of the channels.
Collapse
|
224
|
Gu R, Chen X, Zhou Y, Yuan L. Isolation and characterization of three maize aquaporin genes, ZmNIP2;1, ZmNIP2;4 and ZmTIP4;4 involved in urea transport. BMB Rep 2012; 45:96-101. [PMID: 22360887 DOI: 10.5483/bmbrep.2012.45.2.96] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Urea-based nitrogen fertilizer was widely utilized in maize production, but transporters involved in urea uptake, translocation and cellular homeostasis have not been identified. Here, we isolated three maize aquapoin genes, ZmNIP2;1, ZmNIP2;4 and ZmTIP4;4, from a cDNA library by heterogeneous complementation of a urea uptake-defective yeast. ZmNIP2;1 and ZmNIP2;4 belonged to the nodulin 26-like intrinsic proteins (NIPs) localized at plasma membrane, and ZmTIP4;4 belonged to the tonoplast intrinsic protein (TIPs) at vacuolar membrane. Quantitative RT-PCR revealed that ZmNIP2;1 was expressed constitutively in various organs while ZmNIP2;4 and ZmTIP4;4 transcripts were abundant in reproductive organs and roots. Expression of ZmTIP4;4 was significantly increased in roots and expanded leaves under nitrogen starvation, while those of ZmNIP2;1 and ZmNIP2;4 remained unaffected. Functions of maize aquapoin genes in urea transport together with their distinct expression manners suggested that they might play diverse roles on urea uptake and translocation, or equilibrating urea concentration across tonoplast.
Collapse
Affiliation(s)
- Riliang Gu
- Department of Plant Nutrition, Key Laboratory of Plant-Soil Interactions, MOE, College of Environmental and Resources Sciences, China Agricultural University, Beijing 100193, China
| | | | | | | |
Collapse
|
225
|
Ruiz-Lozano JM, Porcel R, Azcón C, Aroca R. Regulation by arbuscular mycorrhizae of the integrated physiological response to salinity in plants: new challenges in physiological and molecular studies. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:4033-44. [PMID: 22553287 DOI: 10.1093/jxb/ers126] [Citation(s) in RCA: 202] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Excessive salt accumulation in soils is a major ecological and agronomical problem, in particular in arid and semi-arid areas. Excessive soil salinity affects the establishment, development, and growth of plants, resulting in important losses in productivity. Plants have evolved biochemical and molecular mechanisms that may act in a concerted manner and constitute the integrated physiological response to soil salinity. These include the synthesis and accumulation of compatible solutes to avoid cell dehydration and maintain root water uptake, the regulation of ion homeostasis to control ion uptake by roots, compartmentation and transport into shoots, the fine regulation of water uptake and distribution to plant tissues by the action of aquaporins, the reduction of oxidative damage through improved antioxidant capacity and the maintenance of photosynthesis at values adequate for plant growth. Arbuscular mycorrhizal (AM) symbiosis can help the host plants to cope with the detrimental effects of high soil salinity. There is evidence that AM symbiosis affects and regulates several of the above mentioned mechanisms, but the molecular bases of such effects are almost completely unknown. This review summarizes current knowledge about the effects of AM symbiosis on these physiological mechanisms, emphasizing new perspectives and challenges in physiological and molecular studies on salt-stress alleviation by AM symbiosis.
Collapse
Affiliation(s)
- Juan Manuel Ruiz-Lozano
- Dpto Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín (CSIC), Profesor Albareda 1, 18008, Granada, Spain.
| | | | | | | |
Collapse
|
226
|
Lee SH, Chung GC, Jang JY, Ahn SJ, Zwiazek JJ. Overexpression of PIP2;5 aquaporin alleviates effects of low root temperature on cell hydraulic conductivity and growth in Arabidopsis. PLANT PHYSIOLOGY 2012; 159:479-88. [PMID: 22434042 PMCID: PMC3375980 DOI: 10.1104/pp.112.194506] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 03/19/2012] [Indexed: 05/18/2023]
Abstract
The effects of low root temperature on growth and root cell water transport were compared between wild-type Arabidopsis (Arabidopsis thaliana) and plants overexpressing plasma membrane intrinsic protein 1;4 (PIP1;4) and PIP2;5. Descending root temperature from 25°C to 10°C quickly reduced cell hydraulic conductivity (L(p)) in wild-type plants but did not affect L(p) in plants overexpressing PIP1;4 and PIP2;5. Similarly, when the roots of wild-type plants were exposed to 10°C for 1 d, L(p) was lower compared with 25°C. However, there was no effect of low root temperature on L(p) in PIP1;4- and PIP2;5-overexpressing plants after 1 d of treatment. When the roots were exposed to 10°C for 5 d, L(p) was reduced in wild-type plants and in plants overexpressing PIP1;4, whereas there was still no effect in PIP2;5-overexpressing plants. These results suggest that the gating mechanism in PIP1;4 may be more sensitive to prolonged low temperature compared with PIP2;5. The reduction of L(p) at 10°C in roots of wild-type plants was partly restored to the preexposure level by 5 mm Ca(NO(3))(2) and protein phosphatase inhibitors (75 nm okadaic acid or 1 μm Na(3)VO(4)), suggesting that aquaporin phosphorylation/dephosphorylation processes were involved in this response. The temperature sensitivity of cell water transport in roots was reflected by a reduction in shoot and root growth rates in the wild-type and PIP1;4-overexpressing plants exposed to 10°C root temperature for 5 d. However, low root temperature had no effect on growth in plants overexpressing PIP2;5. These results provide strong evidence for a link between growth at low root temperature and aquaporin-mediated root water transport in Arabidopsis.
Collapse
Affiliation(s)
- Seong Hee Lee
- Department of Renewable Resources, University of Alberta, T6G 2E3 Edmonton, Alberta, Canada (S.H.L., J.Y.J., J.J.Z.); and Division of Plant Biotechnology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Korea (G.C.C., S.J.A.)
| | - Gap Chae Chung
- Department of Renewable Resources, University of Alberta, T6G 2E3 Edmonton, Alberta, Canada (S.H.L., J.Y.J., J.J.Z.); and Division of Plant Biotechnology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Korea (G.C.C., S.J.A.)
| | - Ji Young Jang
- Department of Renewable Resources, University of Alberta, T6G 2E3 Edmonton, Alberta, Canada (S.H.L., J.Y.J., J.J.Z.); and Division of Plant Biotechnology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Korea (G.C.C., S.J.A.)
| | - Sung Ju Ahn
- Department of Renewable Resources, University of Alberta, T6G 2E3 Edmonton, Alberta, Canada (S.H.L., J.Y.J., J.J.Z.); and Division of Plant Biotechnology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Korea (G.C.C., S.J.A.)
| | - Janusz J. Zwiazek
- Department of Renewable Resources, University of Alberta, T6G 2E3 Edmonton, Alberta, Canada (S.H.L., J.Y.J., J.J.Z.); and Division of Plant Biotechnology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500–757, Korea (G.C.C., S.J.A.)
| |
Collapse
|
227
|
Lawrence SD, Novak NG, Kayal WE, Ju CJT, Cooke JEK. Root herbivory: molecular analysis of the maize transcriptome upon infestation by Southern corn rootworm, Diabrotica undecimpunctata howardi. PHYSIOLOGIA PLANTARUM 2012; 144:303-19. [PMID: 22172013 DOI: 10.1111/j.1399-3054.2011.01557.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
While many studies have characterized changes to the transcriptome of plants attacked by shoot-eating insect pests, few have examined transcriptome-level effects of root pests. Maize (Zea mays) seedlings were subjected to infestation for approximately 2 weeks by the root herbivore southern corn rootworm (SCR) Diabrotica undecimpunctata howardi, and changes in transcript abundance within both roots and shoots were analyzed using a 57K element microarray. A total of 541 genes showed statistically significant changes in transcript abundance in infested roots, including genes encoding many pathogenesis-related proteins such as chitinases, proteinase inhibitors, peroxidases and β-1,3-glucanases. Several WRKY transcription factors--often associated with biotic responses--exhibited increased transcript abundance upon SCR feeding. Differentially expressed (DE) genes were also detected in shoots of infested vs control plants. Quantitative Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) was used to confirm patterns of transcript abundance for several significant DE genes using an independent experiment with a 2-6 day period of SCR infestation. Because of the well-documented roles that jasmonic acid (JA) or salicylic acid (SA) play in herbivory responses, the effect of exogenous JA or SA application on transcript abundance corresponding to the same subset of SCR-responsive genes was assessed. The response of these genes at the level of transcript abundance to SA and JA differed between roots and shoots and also differed among the genes that were examined. These data suggested that SA- and JA-dependent and independent signals contributed to the transcriptome-level changes in maize roots and shoots in response to SCR infestation.
Collapse
Affiliation(s)
- Susan D Lawrence
- Invasive Insect Biocontrol and Behavior Laboratory, USDA-ARS, BARC-West, 10,300 Baltimore Avenue, Building 011A, Room 214, Beltsville, MD 20705, USA.
| | | | | | | | | |
Collapse
|
228
|
Baaziz KB, Lopez D, Rabot A, Combes D, Gousset A, Bouzid S, Cochard H, Sakr S, Venisse JS. Light-mediated K(leaf) induction and contribution of both the PIP1s and PIP2s aquaporins in five tree species: walnut (Juglans regia) case study. TREE PHYSIOLOGY 2012; 32:423-434. [PMID: 22544048 DOI: 10.1093/treephys/tps022] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Understanding the response of leaf hydraulic conductance (K(leaf)) to light is a challenge in elucidating plant-water relationships. Recent data have shown that the effect of light on K(leaf) is not systematically related to aquaporin regulation, leading to conflicting conclusions. Here we investigated the relationship between light, K(leaf), and aquaporin transcript levels in five tree species (Juglans regia L., Fagus sylvatica L., Quercus robur L., Salix alba L. and Populus tremula L.) grown in the same environmental conditions, but differing in their K(leaf) responses to light. Moreover, the K(leaf) was measured by two independent methods (high-pressure flow metre (HPFM) and evaporative flux method (EFM)) in the most (J. regia) and least (S. alba) responsive species and the transcript levels of aquaporins were analyzed in perfused and unperfused leaves. Here, we found that the light-induced K(leaf) value was closely related to stronger expression of both the PIP1 and PIP2 aquaporin genes in walnut (J. regia), but to stimulation of PIP1 aquaporins alone in F. sylvatica and Q. robur. In walnut, all newly identified aquaporins were found to be upregulated in the light and downregulated in the dark, further supporting the relationship between the light-mediated induction of K(leaf) and aquaporin expression in walnut. We also demonstrated that the K(leaf) response to light was quality-dependent, K(leaf) being 60% lower in the absence of blue light. This decrease in K(leaf) was correlated with strong downregulation of three PIP2 aquaporins and of all the PIP1 aquaporins tested. These data support a relationship between light-mediated K(leaf) regulation and the abundance of aquaporin transcripts in the walnut tree.
Collapse
Affiliation(s)
- Khaoula Ben Baaziz
- Clermont Université, Université Blaise Pascal, UMR547 PIAF, BP 10448, F-63000 Clermont-Ferrand, France
| | | | | | | | | | | | | | | | | |
Collapse
|
229
|
Lopez D, Bronner G, Brunel N, Auguin D, Bourgerie S, Brignolas F, Carpin S, Tournaire-Roux C, Maurel C, Fumanal B, Martin F, Sakr S, Label P, Julien JL, Gousset-Dupont A, Venisse JS. Insights into Populus XIP aquaporins: evolutionary expansion, protein functionality, and environmental regulation. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:2217-30. [PMID: 22223812 DOI: 10.1093/jxb/err404] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A novel category of major intrinsic proteins which share weak similarities with previously identified aquaporin subfamilies was recently identified in land plants, and named X (for unrecognized) intrinsic proteins (XIPs). Because XIPs are still ranked as uncharacterized proteins, their further molecular characterization is required. Herein, a systematic fine-scale analysis of XIP sequences found in flowering plant databases revealed that XIPs are found in at least five groups. The phylogenetic relationship of these five groups with the phylogenetic organization of angiosperms revealed an original pattern of evolution for the XIP subfamily through distinct angiosperm taxon-specific clades. Of all flowering plant having XIPs, the genus Populus encompasses the broadest panel and the highest polymorphism of XIP isoforms, with nine PtXIP sequences distributed within three XIP groups. Comprehensive PtXIP gene expression patterns showed that only two isoforms (PtXIP2;1 and PtXIP3;2) were transcribed in vegetative tissues. However, their patterns are contrasted, PtXIP2;1 was ubiquitously accumulated whereas PtXIP3;2 was predominantly detected in wood and to a lesser extent in roots. Furthermore, only PtXIP2;1 exhibited a differential expression in leaves and stems of drought-, salicylic acid-, or wounding-challenged plants. Unexpectedly, the PtXIPs displayed different abilities to alter water transport upon expression in Xenopus laevis oocytes. PtXIP2;1 and PtXIP3;3 transported water while other PtXIPs did not.
Collapse
Affiliation(s)
- D Lopez
- Université Blaise Pascal UMRA 547 PIAF, Clermont-Ferrand, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
230
|
El Karkouri K, Gueuné H, Delamarche C. MIPDB: a relational database dedicated to MIP family proteins. Biol Cell 2012; 97:535-43. [PMID: 15850453 DOI: 10.1042/bc20040123] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND INFORMATION The MIPs (major intrinsic proteins) constitute a large family of membrane proteins that facilitate the passive transport of water and small neutral solutes across cell membranes. Since water is the most abundant molecule in all living organisms, the discovery of selective water-transporting channels called AQPs (aquaporins) has led to new knowledge on both the physiological and molecular mechanisms of membrane permeability. The MIPs are identified in Archaea, Bacteria and Eukaryota, and the rapid accumulation of new sequences in the database provides an opportunity for large-scale analysis, to identify functional and/or structural signatures or to infer evolutionary relationships. To help perform such an analysis, we have developed MIPDB (database for MIP proteins), a relational database dedicated to members of the MIP family. RESULTS MIPDB is a motif-oriented database that integrates data on 785 MIP proteins from more than 200 organisms and contains 230 distinct sequence motifs. MIPDB proposes the classification of MIP proteins into three functional subgroups: AQPs, glycerol-uptake facilitators and aquaglyceroporins. Plant MIPs are classified into three specific subgroups according to their subcellular distribution in the plasma membrane, tonoplast or the symbiosome membrane. Some motifs of the database are highly selective and can be used to predict the transport function or subcellular localization of unknown MIP proteins. CONCLUSIONS MIPDB offers a user-friendly and intuitive interface for a rapid and easy access to MIP resources and to sequence analysis tools. MIPDB is a web application, publicly accessible at http://idefix.univ-rennes1.fr:8080/Prot/index.html.
Collapse
Affiliation(s)
- Khalid El Karkouri
- UMR CNRS 6026 Interactions Cellulaires et Moléculaires, Université de Rennes 1, équipe SDM (Structure et Dynamique des Macromolécules), Campus de Beaulieu, Bât. 13, 35042 Rennes Cedex, France
| | | | | |
Collapse
|
231
|
Sutka M, Alleva K, Parisi M, Amodeo G. Tonoplast vesicles of Beta vulgaris storage root show functional aquaporins regulated by protons. Biol Cell 2012; 97:837-46. [PMID: 15859949 DOI: 10.1042/bc20040121] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND INFORMATION Water is crucial for plant development and growth, and its transport pathways inside a plant are an ongoing topic for study. Plants express a large number of membrane intrinsic proteins whose role is now being re-evaluated by considering not only the control of the overall plant water balance but also in adaptation to environmental challenges that may affect their physiology. In particular, we focused our work on water movements across the root cell TP (tonoplast), the delimiting membrane of the vacuole. This major organelle plays a central role in osmoregulation. RESULTS An enriched fraction of TP vesicles from Beta vulgaris (red beet) storage roots obtained by a conventional method was used to characterize its water permeability properties by means of the stopped-flow technique. The preparation showed high water permeability (485 microm x s(-1)), consistent with values reported in the literature. The water permeability was strongly blocked by HgCl(2) (reduced to 16%) and its energy activation was low. These observations allow us to postulate the presence of functional water channels in this preparation. Moreover, Western-blot analysis demonstrated the presence of a tonoplast intrinsic protein. With the purpose of studying the regulation of water channels, TP vesicles were exposed to different acidic pH media. When the pH of a medium was low (pH 5.6), the water permeability exhibited a 42% inhibition. CONCLUSIONS Our findings prove that although almost all water channels present in the TP vesicles of B. vulgaris root are sensitive to HgCl(2), not all are inhibited by pH. This interesting selectivity to acidification of the medium could play a role in adapting the water balance in the cell-to-cell pathway.
Collapse
Affiliation(s)
- Moira Sutka
- Laboratorio de Biomembranas, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Piso 7 (C1121ABG), Buenos Aires, Argentina
| | | | | | | |
Collapse
|
232
|
Abstract
BACKGROUND INFORMATION MIPs (major intrinsic proteins) form channels across biological membranes that control recruitment of water and small solutes such as glycerol and urea in all living organisms. Because of their widespread occurrence and large number, MIPs are a sound model system to understand evolutionary mechanisms underlying the generation of protein structural and functional diversity. With the recent increase in genomic projects, there is a considerable increase in the quantity and taxonomic range of MIPs in molecular databases. RESULTS In the present study, I compiled more than 450 non-redundant amino acid sequences of MIPs from NCBI databases. Phylogenetic analyses using Bayesian inference reconstructed a statistically robust tree that allowed the classification of members of the family into two main evolutionary groups, the GLPs (glycerol-uptake facilitators or aquaglyceroporins) and the water transport channels or AQPs (aquaporins). Separate phylogenetic analyses of each of the MIP subfamilies were performed to determine the main groups of orthology. In addition, comparative sequence analyses were conducted to identify conserved signatures in the MIP molecule. CONCLUSIONS The earliest and major gene duplication event in the history of the MIP family led to its main functional split into GLPs and AQPs. GLPs show typically one single copy in microbes (eubacteria, archaea and fungi), up to four paralogues in vertebrates and they are absent from plants. AQPs are usually single in microbes and show their greatest numbers and diversity in angiosperms and vertebrates. Functional recruitment of NOD26-like intrinsic proteins to glycerol transport due to the absence of GLPs in plants was highly supported. Acquisition of other MIP functions such as permeability to ammonia, arsenite or CO2 is restricted to particular MIP paralogues. Up to eight fairly conserved boxes were inferred in the primary sequence of the MIP molecule. All of them mapped on to one side of the channel except the conserved glycine residues from helices 2 and 5 that were found in the opposite side.
Collapse
Affiliation(s)
- Rafael Zardoya
- Departamento de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal, 2, 28006 Madrid, Spain
| |
Collapse
|
233
|
Fraysse LC, Wells B, McCann MC, Kjellbom P. Specific plasma membrane aquaporins of the PIP1 subfamily are expressed in sieve elements and guard cells. Biol Cell 2012; 97:519-34. [PMID: 15898953 DOI: 10.1042/bc20040122] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND INFORMATION Transmembrane water flow is aided by water-specific channel proteins, aquaporins. Plant genomes code for approx. 35 expressed and functional aquaporin isoforms. Plant aquaporins fall into four different subfamilies of which the PIPs (plasma membrane intrinsic proteins) constitute the largest and evolutionarily most conserved subfamily with 13 members in Arabidopsis and maize. Furthermore, the PIPs can be divided into two phylogenetic groups, PIP1 and PIP2, of which the PIP1 isoforms are most tightly conserved, sharing >90% amino acid sequence identity. As the nomenclature implies, the majority of PIPs have been shown to be localized at the plasma membrane. Recently, two highly abundant plasma membrane aquaporins, SoPIP2;1 and SoPIP1;2, have been purified and structurally characterized. RESULTS We report the cloning of a cDNA encoding SoPIP1;2 and show that there are at least five additional sequences homologous with SoPIP2;1 and SoPIP1;2 in the spinach genome. To understand their role in planta, we have investigated the cellular localization of the aquaporin homologues SoPIP1;2 and SoPIP1;1. By Western- and Northern-blot analyses and by immunocytochemical detection at the light and electron microscopic levels, we show that SoPIP1;2 is highly expressed in phloem sieve elements of leaves, roots and petioles and that SoPIP1;1 is present in stomatal guard cells. CONCLUSIONS Localization of the two abundant aquaporin isoforms suggests roles for specific PIPs of the PIP1 subgroup in phloem loading, transport and unloading, and in stomatal movements.
Collapse
Affiliation(s)
- Laure C Fraysse
- Department of Plant Biochemistry, Lund University, P.O. Box 124, S-22100 Lund, Sweden
| | | | | | | |
Collapse
|
234
|
Gupta AB, Verma RK, Agarwal V, Vajpai M, Bansal V, Sankararamakrishnan R. MIPModDB: a central resource for the superfamily of major intrinsic proteins. Nucleic Acids Res 2012; 40:D362-9. [PMID: 22080560 PMCID: PMC3245135 DOI: 10.1093/nar/gkr914] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 10/05/2011] [Accepted: 10/08/2011] [Indexed: 12/23/2022] Open
Abstract
The channel proteins belonging to the major intrinsic proteins (MIP) superfamily are diverse and are found in all forms of life. Water-transporting aquaporin and glycerol-specific aquaglyceroporin are the prototype members of the MIP superfamily. MIPs have also been shown to transport other neutral molecules and gases across the membrane. They have internal homology and possess conserved sequence motifs. By analyzing a large number of publicly available genome sequences, we have identified more than 1000 MIPs from diverse organisms. We have developed a database MIPModDB which will be a unified resource for all MIPs. For each MIP entry, this database contains information about the source, gene structure, sequence features, substitutions in the conserved NPA motifs, structural model, the residues forming the selectivity filter and channel radius profile. For selected set of MIPs, it is possible to derive structure-based sequence alignment and evolutionary relationship. Sequences and structures of selected MIPs can be downloaded from MIPModDB database which is freely available at http://bioinfo.iitk.ac.in/MIPModDB.
Collapse
Affiliation(s)
- Anjali Bansal Gupta
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016 and Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Ravi Kumar Verma
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016 and Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Vatsal Agarwal
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016 and Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Manu Vajpai
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016 and Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Vivek Bansal
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016 and Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Ramasubbu Sankararamakrishnan
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016 and Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, India
| |
Collapse
|
235
|
Rogers JC. Internal membranes in maize aleurone protein storage vacuoles: beyond autophagy. THE PLANT CELL 2011; 23:4168-71; author reply 4171-2. [PMID: 22180629 PMCID: PMC3270317 DOI: 10.1105/tpc.111.092551] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
|
236
|
Ma P, Liu J. Isolation and characterization of a novel plasma membrane intrinsic protein gene, LcPIP1, in Leymus chinensis that enhances salt stress tolerance in Saccharomyces cerevisiae. Appl Biochem Biotechnol 2011; 166:479-85. [PMID: 22072142 DOI: 10.1007/s12010-011-9443-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 10/26/2011] [Indexed: 10/15/2022]
Abstract
A novel plasma membrane intrinsic, LcPIP1, was isolated from Leymus chinensis using RACE method. The LcPIP1 has 288 amino acids with an estimated molecular mass of 30.6 kDa. Semi RT-PCR analysis indicated that the expression level of LcPIP1 was obviously higher in leaf than root. The LcPIP1 was also found to be induced by salt stress. In addition, transformed with the LcPIP1, Saccharomyces cerevisiae could increase tolerance to salt stress. These results indicate that the LcPIP1 gene seems to play a role in resistance against salt stress.
Collapse
Affiliation(s)
- Pengda Ma
- College of Life Sciences, Northwest A & F University, Yangling 712100, People's Republic of China
| | | |
Collapse
|
237
|
Azad AK, Yoshikawa N, Ishikawa T, Sawa Y, Shibata H. Substitution of a single amino acid residue in the aromatic/arginine selectivity filter alters the transport profiles of tonoplast aquaporin homologs. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1818:1-11. [PMID: 21963407 DOI: 10.1016/j.bbamem.2011.09.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Revised: 09/12/2011] [Accepted: 09/13/2011] [Indexed: 11/30/2022]
Abstract
Aquaporins are integral membrane proteins that facilitate the transport of water and some small solutes across cellular membranes. X-ray crystallography of aquaporins indicates that four amino acids constitute an aromatic/arginine (ar/R) pore constriction known as the selectivity filter. On the basis of these four amino acids, tonoplast aquaporins called tonoplast intrinsic proteins (TIPs) are divided into three groups in Arabidopsis. Herein, we describe the characterization of two group I TIP1s (TgTIP1;1 and TgTIP1;2) from tulip (Tulipa gesneriana). TgTIP1;1 and TgTIP1;2 have a novel isoleucine in loop E (LE2 position) of the ar/R filter; the residue at LE2 is a valine in all group I TIPs from model plants. The homologs showed mercury-sensitive water channel activity in a fast kinetics swelling assay upon heterologous expression in Pichia pastoris. Heterologous expression of both homologs promoted the growth of P. pastoris on ammonium or urea as sole sources of nitrogen and decreased growth and survival in the presence of H(2)O(2). TgTIP1;1- and TgTIP1;2-mediated H(2)O(2) conductance was demonstrated further by a fluorescence assay. Substitutions in the ar/R selectivity filter of TgTIP1;1 showed that mutants that mimicked the ar/R constriction of group I TIPs could conduct the same substrates that were transported by wild-type TgTIP1;1. In contrast, mutants that mimicked group II TIPs showed no evidence of urea or H(2)O(2) conductance. These results suggest that the amino acid residue at LE2 position is critical for the transport selectivity of the TIP homologs and group I TIPs might have a broader spectrum of substrate selectivity than group II TIPs.
Collapse
Affiliation(s)
- Abul Kalam Azad
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan.
| | | | | | | | | |
Collapse
|
238
|
Ayadi M, Cavez D, Miled N, Chaumont F, Masmoudi K. Identification and characterization of two plasma membrane aquaporins in durum wheat (Triticum turgidum L. subsp. durum) and their role in abiotic stress tolerance. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2011; 49:1029-39. [PMID: 21723739 DOI: 10.1016/j.plaphy.2011.06.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 06/02/2011] [Indexed: 05/21/2023]
Abstract
Plant plasma membrane intrinsic proteins (PIP) cluster in two phylogenetic groups, PIP1 and PIP2 that have different water channel activities when expressed in Xenopus oocytes. PIP2s induce a marked increase of the membrane osmotic water-permeability coefficient (P(f)), whereas PIP1s are generally inactive. Here we report the cloning of two durum wheat (Triticum turgidum L. subsp. durum) cDNAs encoding TdPIP1;1 and TdPIP2;1 belonging to the PIP1 and PIP2 subfamilies, respectively. Contrary to TdPIP1;1, expression of TdPIP2;1 in Xenopus oocytes resulted in an increase in P(f) compared to water-injected oocytes. Co-expression of the non-functional TdPIP1;1 and the functional TdPIP2;1 lead to a significant increase in P(f) compared with oocytes expressing TdPIP2;1 alone. A truncated form of TdPIP2;1, tdpip2;1, missing the first two transmembrane domains, had no water channel activity. Nonetheless, its co-expression with the functional TdPIP2;1 partially inhibits the P(f) and disrupt the activities of plant aquaporins. In contrast to the approach developed in Xenopus oocytes, phenotypic analyses of transgenic tobacco plants expressing TdPIP1;1 or TdPIP2;1 generated a tolerance phenotype towards osmotic and salinity stress. TdPIP1;1 and TdPIP2;1 are differentially regulated in roots and leaves in the salt-tolerant wheat variety when challenged with salt stress and abscisic acid. Confocal microscopy analysis of tobacco roots expressing TdPIP1;1 and TdPIP2;1 fused to the green fluorescent protein showed that the proteins were localized at the plasma membrane.
Collapse
Affiliation(s)
- Malika Ayadi
- Plant Protection and Improvement Laboratory, Centre of Biotechnology of Sfax, University of Sfax, Route Sidi Mansour Km 6, BP 1177, 3018 Sfax, Tunisia
| | | | | | | | | |
Collapse
|
239
|
Wang X, Li Y, Ji W, Bai X, Cai H, Zhu D, Sun XL, Chen LJ, Zhu YM. A novel Glycine soja tonoplast intrinsic protein gene responds to abiotic stress and depresses salt and dehydration tolerance in transgenic Arabidopsis thaliana. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:1241-8. [PMID: 21397356 DOI: 10.1016/j.jplph.2011.01.016] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 01/19/2011] [Accepted: 01/19/2011] [Indexed: 05/19/2023]
Abstract
Tonoplast intrinsic protein (TIP) is a subfamily of the aquaporin (AQP), also known as major intrinsic protein (MIP) family, and regulates water movement across vacuolar membranes. Some reports have implied that TIP genes are associated with plant tolerance to some abiotic stresses that cause water loss, such as drought and high salinity. In our previous work, we found that an expressed sequence tag (EST) representing a TIP gene in our Glycine soja EST library was inducible by abiotic stresses. This TIP was subsequently isolated from G. soja with cDNA library screening, EST assembly and PCR, and named as GsTIP2;1. The expression patterns of GsTIP2;1 in G. soja under low temperature, salt and dehydration stress were different in leaves and roots. Though GsTIP2;1 is a stress-induced gene, overexpression of GsTIP2;1 in Arabidopsis thaliana depressed tolerance to salt and dehydration stress, but did not affect seedling growth under cold or favorable conditions. Higher dehydration speed was detected in Arabidopsis plants overexpressing GsTIP2;1, implying GsTIP2;1 might mediate stress sensitivity by enhancing water loss in the plant. Such a result is not identical to previous reports, providing some new information about the relationship between TIP and plant abiotic stress tolerance.
Collapse
Affiliation(s)
- Xi Wang
- Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin, China
| | | | | | | | | | | | | | | | | |
Collapse
|
240
|
Sakurai-Ishikawa J, Murai-Hatano M, Hayashi H, Ahamed A, Fukushi K, Matsumoto T, Kitagawa Y. Transpiration from shoots triggers diurnal changes in root aquaporin expression. PLANT, CELL & ENVIRONMENT 2011; 34:1150-63. [PMID: 21414014 DOI: 10.1111/j.1365-3040.2011.02313.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Root hydraulic conductivity (Lp(r)) and aquaporin amounts change diurnally. Previously, these changes were considered to be spontaneously driven by a circadian rhythm. Here, we evaluated the new hypothesis that diurnal changes could be triggered and enhanced by transpirational demand from shoots. When rice plants were grown under a 12h light/12h dark regime, Lp(r) was low in the dark and high in the light period. Root aquaporin mRNA levels also changed diurnally, but the amplitudes differed among aquaporin isoforms. Aquaporins, such as OsPIP2;1, showed moderate changes, whereas root-specific aquaporins, such as OsPIP2;5, showed temporal and dramatic induction around 2h after light initiation. When darkness was extended for 12h after the usual dark period, no such induction was observed. Furthermore, plants under 100% relative humidity (RH) showed no induction even in the presence of light. These results suggest that transpirational demand triggers a dramatic increase in gene expressions such as OsPIP2;5. Immunocytochemistry showed that OsPIP2;5 accumulated on the proximal end of the endodermis and of the cell surface around xylem. The strong induction by transpirational demand and the polar localization suggest that OsPIP2;5 contributes to fine adjustment of radial water transport in roots to sustain high Lp(r) during the day.
Collapse
Affiliation(s)
- Junko Sakurai-Ishikawa
- Climate Change Research Team, National Agricultural Research Center for Tohoku Region, Morioka, Japan
| | | | | | | | | | | | | |
Collapse
|
241
|
Bae EK, Lee H, Lee JS, Noh EW. Drought, salt and wounding stress induce the expression of the plasma membrane intrinsic protein 1 gene in poplar (Populus alba×P. tremula var. glandulosa). Gene 2011; 483:43-8. [PMID: 21640804 DOI: 10.1016/j.gene.2011.05.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 05/17/2011] [Indexed: 10/18/2022]
Abstract
Water uptake across cell membranes is a principal requirement for plant growth at both the cellular and whole-plant levels; water movement through plant membranes is regulated by aquaporins (AQPs) or major intrinsic proteins (MIPs). We examined the expression characteristics of the poplar plasma membrane intrinsic protein 1 gene (PatPIP1), a type of MIP, which was isolated from a suspension cell cDNA library of Populus alba×P. tremula var. glandulosa. Examination of protoplasts expressing the p35S-PatPIP1::sGFP fusion protein revealed that the protein was localized in the plasma membrane. Northern blot analysis revealed that the gene was strongly expressed in poplar roots and leaves. Gene expression was inducible by abiotic factors including drought, salinity, cold temperatures and wounding, and also by plant hormones including gibberellic acid, jasmonic acid and salicylic acid. Since we found that the PatPIP1 gene was strongly expressed in response to mannitol, NaCl, jasmonic acid and wounding, we propose that PatPIP1 plays an essential role in the defense of plants against water stress.
Collapse
Affiliation(s)
- Eun-Kyung Bae
- Biotechnology Division, Korea Forest Research Institute, Suwon, Republic of Korea
| | | | | | | |
Collapse
|
242
|
Tavares B, Domingos P, Dias PN, Feijó JA, Bicho A. The essential role of anionic transport in plant cells: the pollen tube as a case study. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:2273-2298. [PMID: 21511914 DOI: 10.1093/jxb/err036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Plasma membrane anion transporters play fundamental roles in plant cell biology, especially in stomatal closure and nutrition. Notwithstanding, a lot is still unknown about the specific function of these transporters, their specific localization, or molecular nature. Here the fundamental roles of anionic transport in plant cells are reviewed. Special attention will be paid to them in the control of pollen tube growth. Pollen tubes are extreme examples of cellular polarity as they grow exclusively in their apical extremity. Their unique cell biology has been extensively exploited for fundamental understanding of cellular growth and morphogenesis. Non-invasive methods have demonstrated that tube growth is governed by different ion fluxes, with different properties and distribution. Not much is known about the nature of the membrane transporters responsible for anionic transport and their regulation in the pollen tube. Recent data indicate the importance of chloride (Cl(-)) transfer across the plasma membrane for pollen germination and pollen tube growth. A general overview is presented of the well-known accumulated data in terms of biophysical and functional characterization, transcriptomics, and genomic description of pollen ionic transport, and the various controversies around the role of anionic fluxes during pollen tube germination, growth, and development. It is concluded that, like all other plant cells so far analysed, pollen tubes depend on anion fluxes for a number of fundamental homeostatic properties.
Collapse
|
243
|
Bienert GP, Bienert MD, Jahn TP, Boutry M, Chaumont F. Solanaceae XIPs are plasma membrane aquaporins that facilitate the transport of many uncharged substrates. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 66:306-17. [PMID: 21241387 DOI: 10.1111/j.1365-313x.2011.04496.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Major intrinsic proteins (MIPs) transport water and uncharged solutes across membranes in all kingdoms of life. Recently, an uncharacterized MIP subfamily was identified in the genomes of plants and fungi and named X Intrinsic Proteins (XIPs). Here, we describe the genetic features, localization, expression, and functions of a group of Solanaceae XIPs. XIP cDNA and gDNA were cloned from tobacco, potato, tomato, and morning glory. A conserved sequence motif in the first intron of Solanaceae XIPs initiates an RNA-processing mechanism that results in two splice variants (α and β). When transiently or stably expressed in tobacco plants, yellow fluorescent protein-tagged NtXIP1;1α and NtXIP1;1β were both localized in the plasma membrane. Transgenic tobacco lines expressing NtXIP1;1-promoter-GUS constructs and RT-PCR studies showed that NtXIP1;1 was expressed in all organs. The NtXIP1;1 promoter was mainly active in cell layers facing the environment in all above-ground tissues. Heterologous expression of Solanaceae XIPs in Xenopus laevis oocytes and various Saccharomyces cerevisiae mutants demonstrated that these isoforms facilitate the transport of bulky solutes, such as glycerol, urea, and boric acid. In contrast, permeability for water was undetectable. These data suggest that XIPs function in the transport of uncharged solutes across the cell plasma membrane in specific plant tissues, including at the interface between the environment and external cell layers.
Collapse
Affiliation(s)
- Gerd Patrick Bienert
- Institut des Sciences de la Vie, Université Catholique de Louvain, Croix du Sud 4-15, B-1348 Louvain-la-Neuve, Belgium
| | | | | | | | | |
Collapse
|
244
|
Muries B, Faize M, Carvajal M, Martínez-Ballesta MDC. Identification and differential induction of the expression of aquaporins by salinity in broccoli plants. MOLECULAR BIOSYSTEMS 2011; 7:1322-35. [PMID: 21321750 DOI: 10.1039/c0mb00285b] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Plant aquaporins belong to a large superfamily of conserved proteins called the major intrinsic proteins (MIPs). There is limited information about the diversity of MIPs and their water transport capacity in broccoli (Brassica oleracea) plants. In this study, the cDNAs of isoforms of Plasma Membrane Intrinsic Proteins (PIPs), a class of aquaporins, from broccoli roots have been partially sequenced. Thus, sequencing experiments led to the identification of eight PIP1 and three PIP2 genes encoding PIPs in B. oleracea plants. The occurrence of different gene products encoding PIPs suggests that they may play different roles in plants. The screening of their expression as well as the expression of two specific PIP2 isoforms (BoPIP2;2 and BoPIP2;3), in different organs and under different salt-stress conditions in two varieties, has helped to unravel the function and the regulation of PIPs in plants. Thus, a high degree of BoPIP2;3 expression in mature leaves suggests that this BoPIP2;3 isoform plays important roles, not only in root water relations but also in the physiology and development of leaves. In addition, differences between gene and protein patterns led us to consider that mRNA synthesis is inhibited by the accumulation of the corresponding encoded protein. Therefore, transcript levels, protein abundance determination and the integrated hydraulic architecture of the roots must be considered in order to interpret the response of broccoli to salinity.
Collapse
Affiliation(s)
- Beatriz Muries
- Dpto Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Campus de Espinardo, 30100 Murcia, Spain
| | | | | | | |
Collapse
|
245
|
Azad AK, Sato R, Ohtani K, Sawa Y, Ishikawa T, Shibata H. Functional characterization and hyperosmotic regulation of aquaporin in Synechocystis sp. PCC 6803. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2011; 180:375-382. [PMID: 21421383 DOI: 10.1016/j.plantsci.2010.10.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 09/17/2010] [Accepted: 10/19/2010] [Indexed: 05/30/2023]
Abstract
The genome of the cyanobacterium Synechocystis sp. PCC 6803 (hereafter, Synechocystis) contains an aqpZ gene (slr2057) which encodes an aquaporin (SsAqpZ), a membrane channel protein that might play a role in osmotic water transport and therefore the growth of Synechocystis. Structural characterization of SsAqpZ by protein sequence analysis and homology modelling revealed that it was more similar to bacterial aquaporin Z than the glycerol facilitator. To understand the functional role of SsAqpZ, the aqpZ knockout (KO) and myc-tagged aqpZ knockin (KI) Synechocystis were constructed. Water channel activity assays showed that SsAqpZ facilitated water transportation. SsAqpZ-mediated changes in cell volume were observed in wild-type (WT) and KI Synechocystis. Expression of SsAqpZ in KI Synechocystis was induced by extracellular hyperosmolarity. In the absence of hyperosmolarity, WT, KO and KI Synechocystis showed the same pattern of growth and no morphological or phenotypical perturbations. Under hyperosmotic condition, while the WT and also KI cells maintained a similar growth rate throughout the entire exponential phase, KO cells grew significantly slower. These results indicate that SsAqpZ has water channel activity and is involved in the adaptation and maintenance of growth of Synechocystis in a hyperosmotic environment.
Collapse
Affiliation(s)
- Abul Kalam Azad
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan.
| | | | | | | | | | | |
Collapse
|
246
|
Vera-Estrella R, Bohnert HJ. Physiological Roles for the PIP Family of Plant Aquaporins. THE PLANT PLASMA MEMBRANE 2011. [DOI: 10.1007/978-3-642-13431-9_8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
247
|
Plant Aquaporins: Roles in Water Homeostasis, Nutrition, and Signaling Processes. SIGNALING AND COMMUNICATION IN PLANTS 2011. [DOI: 10.1007/978-3-642-14369-4_1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
248
|
Ligaba A, Katsuhara M, Shibasaka M, Djira G. Abiotic stresses modulate expression of major intrinsic proteins in barley (Hordeum vulgare). C R Biol 2010; 334:127-39. [PMID: 21333943 DOI: 10.1016/j.crvi.2010.11.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2010] [Revised: 08/03/2010] [Accepted: 11/12/2010] [Indexed: 11/15/2022]
Abstract
In one of the most important crops, barley (Hordeum vulgare L.), gene expression and physiological roles of most major intrinsic proteins (MIPs) remained to be elucidated. Here we studied expression of five tonoplast intrinsic protein isoforms (HvTIP1;2, HvTIP2;1, HvTIP2;2, HvTIP2;3 and HvTIP4;1), a NOD26-like intrinsic protein (HvNIP2;1) and a plasma membrane intrinsic protein (HvPIP2;1) by using the quantitative real-time RT-PCR. Five-day-old seedlings were exposed to abiotic stresses (salt, heavy metals and nutrient deficiency), abscisic acid (ABA) and gibberellic acid (GA) for 24 h. Treatment with 100 mM NaCl, 0.1 mM ABA and 1 mM GA differentially regulated gene expression in roots and shoots. Nitrogen and prolonged P-deficiency downregulated expression of most MIP genes in roots. Intriguingly, gene expression was restored to the values in the control three days after nutrient supply was resumed. Heavy metals (0.2 mM each of Cd, Cu, Zn and Cr) downregulated the transcript levels by 60-80% in roots, whereas 0.2 mM Hg upregulated expressions of most genes in roots. This was accompanied by a 45% decrease in the rate of transpiration. In order to study the physiological role of the MIPs, cDNA of three genes (HvTIP2;1, HvTIP2;3 and HvNIP2;1) have been cloned and heterologous expression was performed in Xenopus laevis oocytes. Osmotic water permeability was determined by a swelling assay. However, no water uptake activity was observed for the three proteins. Hence, the possible physiological role of the proteins is discussed.
Collapse
Affiliation(s)
- Ayalew Ligaba
- Cornell University, Robert Holley Center, USDA-ARS, Ithaca, New York 14853, USA.
| | | | | | | |
Collapse
|
249
|
Gena P, Pellegrini-Calace M, Biasco A, Svelto M, Calamita G. Aquaporin Membrane Channels: Biophysics, Classification, Functions, and Possible Biotechnological Applications. FOOD BIOPHYS 2010. [DOI: 10.1007/s11483-010-9193-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
250
|
Almeida-Rodriguez AM, Cooke JEK, Yeh F, Zwiazek JJ. Functional characterization of drought-responsive aquaporins in Populus balsamifera and Populus simonii×balsamifera clones with different drought resistance strategies. PHYSIOLOGIA PLANTARUM 2010; 140:321-33. [PMID: 20681973 DOI: 10.1111/j.1399-3054.2010.01405.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We have characterized poplar aquaporins (AQPs) to investigate their possible functions in differential drought responses of Populus balsamifera and Populus simonii×balsamifera leaves. Plants were exposed to mild and severe levels of drought stress and to drought stress recovery treatment, and their responses were compared with well-watered controls. Compared with P. balsamifera, P. simonii×balsamifera used drought avoidance as the main drought resistance strategy, and rapidly reduced stomatal conductance in response to stress. This strategy is correlated with growth rate reductions. Eleven AQPs were transcriptionally profiled in leaves from these experiments and five were functionally characterized for water channel activity. PIP1;3 and PIP2;5 were among the most highly expressed leaf AQPs that were responsive to drought. Expression of PIP1;3 and five other AQPs increased in response to drought in the leaves of P. simonii×balsamifera but not in P. balsamifera, suggesting a possible role of these AQPs in water redistribution in the leaf tissues. PIP2;5 was upregulated in P. balsamifera, but not in P. simonii×balsamifera, suggesting that this AQP supports the transpiration-driven water flow. Functional characterization of five drought-responsive plasma membrane intrinsic proteins (PIPs) demonstrated that three PIP2 AQPs (PIP2;2, PIP2;5, PIP2;7) functioned as water transporters in Xenopus laevis oocytes, while the two PIP1 AQPs (PIP1;2 and PIP1;3) did not, consistent with the notion that they may be functional only as heterotetramers.
Collapse
|