Formation of the Stomatal Outer Cuticular Ledge Requires a Guard Cell Wall Proline-Rich Protein.
Stomata are formed by a pair of guard cells which have thickened, elastic cell walls to withstand the large increases in turgor pressure that have to be generated to open the pore that they surround. We have characterized FOCL1, a guard cell-expressed, secreted protein with homology to Hyp-rich cell wall proteins. FOCL1-GFP localizes to the guard cell outer cuticular ledge and plants lacking FOCL1 produce stomata without a cuticular ledge. Instead the majority of stomatal pores are entirely covered over by a continuous fusion of the cuticle, and consequently plants have decreased levels of transpiration and display drought tolerance. Thefocl1guard cells are larger and less able to reduce the aperture of their stomatal pore in response to closure signals suggesting that the flexibility of guard cell walls is impaired.FOCL1is also expressed in lateral root initials where it aids lateral root emergence. We propose that FOCL1 acts in these highly specialized cells of the stomata and root to impart cell wall strength at high turgor and/or to facilitate interactions between the cell wall and the cuticle.
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Lee
http://orcid.org/0000-0001-6781-0540
L
Hunt
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Samuel
http://orcid.org/0000-0002-2767-9768
S
Amsbury
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Alice
http://orcid.org/0000-0002-3548-6245
A
Baillie
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Mahsa
M
Movahedi
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Alice
A
Mitchell
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Mana
M
Afsharinafar
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Kamal
http://orcid.org/0000-0003-3658-2543
K
Swarup
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Thomas
T
Denyer
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Jamie K
JK
Hobbs
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Ranjan
http://orcid.org/0000-0002-6438-9188
R
Swarup
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.).|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.).|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.).
Andrew J
http://orcid.org/0000-0002-9703-0745
AJ
Fleming
Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom (L.H., M.M., A.M., M.A., J.E.G.); j.e.gray@sheffield.ac.uk.|Department of Animal and Plant Sciences, University of Sheffield, Sheffield S3 7HF, United Kingdom (S.A., A.B., A.J.F.); j.e.gray@sheffield.ac.uk.|Centre for Integrative Plant Biology, University of Nottingham, Nottingham LE12 5RD, United Kingdom (K.S., T.D., R.S.); and j.e.gray@sheffield.ac.uk.|Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom (J.K.H.) j.e.gray@sheffield.ac.uk.
Julie E
http://orcid.org/0000-0001-9972-5156
JE
Gray
D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D059828:Plant Cells / Q000378:metabolism*; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D054046:Plant Stomata / Q000166:cytology* / Q000502:physiology*; D018526:Plant Transpiration / Q000235:genetics; D011392:Proline
D029681:Arabidopsis Proteins; D011392:Proline