The role of the vacuole in the accumulation and mobilization of sucrose

Abstract

The contribution that isolated vacuoles have made to understanding sucrose storage and mobilization is reviewed briefly, with particular reference to the storage root of red beet (Beta vulgaris L.) . Work with isolated vacuoles has shown that in this tissue sucrose is confined to the vacuole and some progress has been made in elucidating the possible mechanism of sucrose transport into the vacuole . The evidence that this is a H' : sucrose antiport, dependent on the activity of a proton-translocating ATPase is examined . It is concluded that while there is some evidence for the presence of a proton pump, a link between this and sucrose uptake has still to be established, Using isolated vacuoles it has been demonstrated that during mobilization of sucrose, hydrolysis occurs within the vacuole but the mechanism of unloading of hexoses from the vacuole remains to be elucidated .

A Genomic Resource for the Development, Improvement, and Exploitation of Sorghum for Bioenergy

“…Additionally, a vacuolar-processing enzyme was identified in this region. Vacuoles serve a major role in sucrose accumulation and mobilization in plants ( Leigh 1984 ). The other region on chromosome 4 contains four genes, one of which, a B-box zinc finger protein, shares homology with a salt tolerance homolog.…”

Valine uptake in the tap root of sugar beet: a comparative analysis with sucrose uptake

“…Nutrients are mainly stored in pericyclic cells (Saftner et al, 1983). In these cells, sucrose is stored in the vacuole and can be released from this compartment only after hydrolysis (Leigh, 1984). In mature sugar beet root, sucrose unloading is apoplastic and uptake and accumulation in the vacuole occur without hydrolysis (Wyse, 1979).…”

Distribution of 14C assimilates in the storage root of sugar beet plants after import from leaves of different age

“…The absence of any noticeable redistribution is not surprising when one considers that 97% of the sucrose is retained in the vacuoles of the storage parenchyma cells (Saftner et al 1983) and that sucrose can only be released from the vacuoles after hydrolysis (Leigh 1984),…”