Use of an in vitro tuberization system to study tuber protein gene expression

Abstract

Nodal cuttings from micropropagated potato plantlets give rise to microtubers when placed on Murashige and Skoog medium containing 6% sucrose and 2.5 mg/liter kinetin and incubated in the dark at 19 degrees C. Microtubers produced from the cultivar Superior were shown to contain the same characteristic group of proteins as field-grown tubers. As with field-grown tubers, the 40,000-dalton major tuber glycoprotein, patatin, accumulated to high levels in microtubers, reaching 3.7 +/- 0.2 mg/g fresh weight after 90 d. Also in agreement with field-grown plants, stems and leaves of micropropagated plantlets did not contain detectable levels of patatin, but small amounts of an electrophoretically distinct form accumulated transiently in roots. Patatin mRNA is readily detectable in developing microtubers 15 d after transfer of the cuttings to inductive medium. Patatin mRNA was also present in roots, but as with field-grown plants, was 50- to 100-fold less abundant and could be distinguished from that in tubers by primer extension. Microtuber development and patatin accumulation were inhibited by gibberellic acid.

Introduction of the carrot HSP17.7 into potato (Solanum tuberosum L.) enhances cellular membrane stability and tuberization in vitro

“…An alternative method of analysis that can be used is in vitro tuberization. Microtubers produced in vitro have been shown to retain similar characteristics in major storage protein synthesis, including patatin, compared with field-grown tubers (Bourque, Miller & Park 1987;Nowak & Colborne 1989). In vitro tuberization is also known to be a reliable indicator in field trials and greenhouse studies for screening potato germplasm for heat stress.…”

Behaviour of plant material issued from in vitro tuberization

“…strain PsJN) effects on the performance of Kennebec (A-E) and Shepody (F) potatoes. A) six-week-old plantlets grown on a hormone-free MS medium; B) four-week-old plantlets transplanted directly from culture vessels to Banting field in Truro, Nova Scotia, and grown for five weeks (July 10, 1990); C) microtubers (on the medium by Bourque et al, 1987) derived from nodal explants bacterized with 3x108 CFU ml l upon insertion into the medium (Bact 1), non-bacterized (Control), and taken from third generation of bacterized stock plants (Bact 3); D,E, F-bacterization and seaweed (Durvillea potatorum) extract amendment (400 ml 85 1 l) effect on stolon production (D), set of 2.5-9.9 g minitubers (E), and root development (F) six weeks after plantlet transplanting to peat-based growing medium (ASB, Pointe Spain, NB, Canada) in a greenhouse; four-week-old plantlets, non-bacterized (1 and 4) and bacterized (2 and 3) in nonamended (1 and 2) and seaweed extract (Seasol) amended (3 and 4) medium.…”

Cytosolic expression of the Bacillus amyloliquefaciens SacB protein inhibits tissue development in transgenic tobacco and potato

“…Transformed plants were selected for kanamycin resistance, transferred to soil and grown to maturity in the greenhouse. In potato, microtubers were produced by the method of Bourque, Moller & Park (1987).…”