CSIRO Publishing Books Journals About Us Shopping Cart You are here: Journals > Functional Plant Biology   
Functional Plant Biology
  Plant Function & Evolutionary Biology
 
Search
 
 
  Advanced Search
   

Journal Home
About the Journal
Editorial Board
Contacts
Content
Online Early
Current Issue
Just Accepted
All Issues
Special Issues
Research Fronts
Reviews
Evolutionary Reviews
Sample Issue
For Authors
General Information
Notice to Authors
Submit Article
Open Access
For Referees
General Information
Review Article
Annual Referee Index
Referee Guidelines
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates

 Early Alert
Subscribe to our email Early Alert or RSS feeds for the latest journal papers.

 Connect with us
facebook   youtube

 PrometheusWiki
PrometheusWiki
Protocols in ecological and environmental plant physiology

 

Article << Previous     |     Next >>   Contents Vol 34(6)

Regulation of invertase: a ‘suite’ of transcriptional and post-transcriptional mechanisms

Li-Fen Huang A B D E, Philip N. Bocock A C E F, John M. Davis A C, Karen E. Koch A B

A Plant Molecular and Cellular Biology Program, PO BOX 110690, University of Florida, Gainesville, FL 32611, USA.
B Department of Horticultural Sciences, PO BOX 110690, University of Florida, Gainesville, FL 32611, USA.
C School of Forest Resources and Conservation, PO BOX 110410, University of Florida, Gainesville, FL 32611, USA.
D Present address: Institute of Molecular Biology, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China.
E These authors contributed equally to this work.
F Corresponding author. Email: pnbocock@ufl.edu
G This paper originates from a presentation at the 8th International Congress of Plant Molecular Biology, Adelaide, Australia, August 2006.
 
PDF (364 KB) $25
 Export Citation
 Print
  


Abstract

Recent evidence indicates that several mechanisms can alter invertase activity and, thus, affect sucrose metabolism and resource allocation in plants. One of these mechanisms is the compartmentalisation of at least some vacuolar invertases in precursor protease vesicles (PPV), where their retention could control timing of delivery to vacuoles and hence activity. PPV are small, ER-derived bodies that sequester a subset of vacuolar-bound proteins (such as invertases and protease precursors) releasing them to acid vacuoles in response to developmental or environmental signals. Another newly-identified effector of invertases is wall-associated kinase 2 (WAK2), which can regulate a specific vacuolar invertase in Arabidopsis (AtvacINV1) and alter root growth when osmolyte supplies are limiting. WAKs are ideally positioned to sense changes in the interface between the cell wall and plasma membrane (such as turgor), because the N-terminus of each WAK extends into the cell wall matrix (where a pectin association is hypothesised) and the C-terminus has a cytoplasmic serine/threonine kinase domain (signalling). Still other avenues of invertase control are provided by a diverse group of kinases and phosphatases, consistent with input from multiple sensing systems for sugars, pathogens, ABA and other hormones. Mechanisms of regulation may also vary for the contrasting sugar responses of different acid invertase transcripts. Some degree of hexokinase involvement and distinctive kinetics have been observed for the sugar-repressed invertases, but not for the more common, sugar-induced forms examined thus far. An additional means of regulation for invertase gene expression lies in the multiple DST (Down STream) elements of the 3′ untranslated region for the most rapidly repressed invertases. Similar sequences were initially identified in small auxin-up RNAs (SAUR) where they mediate rapid mRNA turnover. Finally, the invertase inhibitors, cell wall- and vacuolar inhibitors of fructosidase (CIF and VIF, respectively) are indistinguishable by sequence alone from pectin methylesterase inhibitors (PMEI); however, recent evidence suggests binding specificity may be determined by flexibility of a short, N-terminal region. These recently characterised processes increase the suite of regulatory mechanisms by which invertase – and, thus, sucrose metabolism and resource partitioning – can be altered in plants.

Keywords: cell expansion, inhibitor of fructosidase, pectin methylesterase inhibitor, precursor protein vesicle, RNA stability, sugar sensing, wall-associated kinase.


   
Subscriber Login
Username:
Password:  

    


 
Top  Email this page
 
Legal & Privacy | Contact Us | Help

CSIRO

© CSIRO 1996-2012