PMID- 19520670
OWN - NLM
STAT- MEDLINE
DCOM- 20090821
LR  - 20240109
IS  - 1471-9053 (Electronic)
IS  - 0032-0781 (Linking)
VI  - 50
IP  - 7
DP  - 2009 Jul
TI  - Activation of sucrose transport in defoliated Lolium perenne L.: an example of 
      apoplastic phloem loading plasticity.
PG  - 1329-44
LID - 10.1093/pcp/pcp081 [doi]
AB  - The pathway of carbon phloem loading was examined in leaf tissues of the forage 
      grass Lolium perenne. The effect of defoliation (leaf blade removal) on sucrose 
      transport capacity was assessed in leaf sheaths as the major carbon source for 
      regrowth. The pathway of carbon transport was assessed via a combination of 
      electron microscopy, plasmolysis experiments and plasma membrane vesicles (PMVs) 
      purified by aqueous two-phase partitioning from the microsomal fraction. Results 
      support an apoplastic phloem loading mechanism. Imposition of an artificial 
      proton-motive force to PMVs from leaf sheaths energized an active, transient and 
      saturable uptake of sucrose (Suc). The affinity of Suc carriers for Suc was 580 
      microM in leaf sheaths of undefoliated plants. Defoliation induced a decrease of 
      K(m) followed by an increase of V(max). A transporter was isolated from stubble 
      (including leaf sheaths) cDNA libraries and functionally expressed in yeast. The 
      level of L.perenne SUcrose Transporter 1 (LpSUT1) expression increased in leaf 
      sheaths in response to defoliation. Taken together, the results indicate that Suc 
      transport capacity increased in leaf sheaths of L. perenne in response to leaf 
      blade removal. This increase might imply de novo synthesis of Suc transporters, 
      including LpSUT1, and may represent one of the mechanisms contributing to rapid 
      refoliation.
FAU - Berthier, Alexandre
AU  - Berthier A
AD  - UMR INRA-UCBN 950, Ecophysiologie Vegetale, Agronomie and nutritions NCS, irba, 
      Esplanade de la Paix, Universite de Caen, Caen, France.
FAU - Desclos, Marie
AU  - Desclos M
FAU - Amiard, Veronique
AU  - Amiard V
FAU - Morvan-Bertrand, Annette
AU  - Morvan-Bertrand A
FAU - Demmig-Adams, Barbara
AU  - Demmig-Adams B
FAU - Adams, William W 3rd
AU  - Adams WW 3rd
FAU - Turgeon, Robert
AU  - Turgeon R
FAU - Prud'homme, Marie-Pascale
AU  - Prud'homme MP
FAU - Noiraud-Romy, Nathalie
AU  - Noiraud-Romy N
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20090610
PL  - Japan
TA  - Plant Cell Physiol
JT  - Plant & cell physiology
JID - 9430925
RN  - 0 (Membrane Transport Proteins)
RN  - 0 (Plant Proteins)
RN  - 0 (RNA, Plant)
RN  - 57-50-1 (Sucrose)
SB  - IM
MH  - *Biological Transport
MH  - Gene Library
MH  - Lolium/genetics/growth & development/*metabolism
MH  - Membrane Transport Proteins/genetics/metabolism
MH  - Phloem/*metabolism
MH  - Plant Leaves/growth & development/metabolism
MH  - Plant Proteins/genetics/metabolism
MH  - Proton-Motive Force
MH  - RNA, Plant/genetics
MH  - Sucrose/*metabolism
EDAT- 2009/06/13 09:00
MHDA- 2009/08/22 09:00
CRDT- 2009/06/13 09:00
PHST- 2009/06/13 09:00 [entrez]
PHST- 2009/06/13 09:00 [pubmed]
PHST- 2009/08/22 09:00 [medline]
AID - pcp081 [pii]
AID - 10.1093/pcp/pcp081 [doi]
PST - ppublish
SO  - Plant Cell Physiol. 2009 Jul;50(7):1329-44. doi: 10.1093/pcp/pcp081. Epub 2009 
      Jun 10.