J Integr Plant Biol. ›› 2015, Vol. 57 ›› Issue (4): 373-387.DOI: 10.1111/jipb.12331

• Research Articles • Previous Articles     Next Articles

The biosynthesis and wall-binding of hemicelluloses in cellulose-deficient maize cells: An example of metabolic plasticity

María de Castro1,2, Janice G. Miller1, José Luis Acebes2, Antonio Encina2, Penélope García-Angulo2 and Stephen C. Fry1*   

  1. 1The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, School of Biological Sciences, The King's Buildings, Edinburgh, UK
    2Área de Fisiología Vegetal, Facultad de CC Biológicas y Ambientales, Universidad de León, León, Spain
  • Received:2014-11-28 Accepted:2015-01-19 Published:2015-04-01
  • About author:*Correspondence: E-mail: S.Fry@ed.ac.uk

Abstract:

Cell-suspension cultures (Zea mays L., Black Mexican sweet corn) habituated to 2,6-dichlorobenzonitrile (DCB) survive with reduced cellulose owing to hemicellulose network modification. We aimed to define the hemicellulose metabolism modifications in DCB-habituated maize cells showing a mild reduction in cellulose at different stages in the culture cycle. Using pulse-chase radiolabeling, we fed habituated and non-habituated cultures with [3H]arabinose, and traced the distribution of 3H-pentose residues between xylans, xyloglucans and other polymers in several cellular compartments for 5 h. Habituated cells were slower taking up exogenous [3H]arabinose. Tritium was incorporated into polysaccharide-bound arabinose and xylose residues, but habituated cells diverted a higher proportion of their new [3H]xylose residues into (hetero) xylans at the expense of xyloglucan synthesis. During logarithmic growth, habituated cells showed slower vesicular trafficking of polymers, especially xylans. Moreover, habituated cells showed a decrease in the strong wall-binding of all pentose-containing polysaccharides studied; correspondingly, especially in log-phase cultures, habituation increased the proportion of 3H-hemicelluloses ([3H]xylans and [3H]xyloglucan) sloughed into the medium. These findings could be related to the cell walls' cellulose-deficiency, and consequent reduction in binding sites for hemicelluloses; the data could also reflect the habituated cells' reduced capacity to integrate arabinoxylans by extra-protoplasmic phenolic cross-linking, as well as xyloglucans, during wall assembly.

 

de Castro M, Miller JG, Acebes JL, Encina A, García-Angulo P, Fry SC (2015) The biosynthesis and wall-binding of hemicelluloses in cellulose-deficient maize cells: An example of metabolic plasticity. J Integr Plant Biol 57: 373–387 doi: 10.1111/jipb.12331

Key words: Arabinoxylan, cell wall cross-linking, 2,6-dichlorobenzonitrile, Hemicellulose biosynthesis, xyloglucan

Editorial Office, Journal of Integrative Plant Biology, Institute of Botany, CAS
No. 20 Nanxincun, Xiangshan, Beijing 100093, China
Tel: +86 10 6283 6133 Fax: +86 10 8259 2636 E-mail: jipb@ibcas.ac.cn
Copyright © 2021 by the Institute of Botany, the Chinese Academy of Sciences
Online ISSN: 1744-7909 Print ISSN: 1672-9072 CN: 11-5067/Q
备案号:京ICP备16067583号-22