Drought-Induced Changes in Protein Patterns of Brassica napus var. oleifera Roots

Abstract

ABSTRACIDrought-induced changes in two-dimensional silver stained protein patterns of Brassica napus L. var. oleifera M. root system were detected both at quantitative and qualitative levels. Particularly, 13 new polypeptides of low molecular weight were evidenced in the drought-stressed tap root, 12 of which were also present in the short tuberized roots, a specific drought-induced root type. The reversibility of these modifications, observed after 3 days rehydration, suggests that they might be involved in drought tolerance. a potentiality for drought survival in natural environment (29). Thus, such a system allows not only to examine the effects of water deficit on the protein pattern of normal roots, but also to determine to what extent the new drought-adapted short roots display a peculiar, specific pattern.The two-dimensional electrophoresis of denatured proteins (10,18), which allows to detect simultaneously several hundreds of gene products and to follow the modifications of gene expression in different organs (25,30) and under various conditions, was the valuable tool to such an approach.In this paper we show that reversible changes in protein patterns ofthe tap root ofBrassica napus var. oleifera are induced by drought and that most of the drought specific proteins are also found in the short tuberized roots.In spite of intensive research in the field of water stress and plant physiology, few drought-induced changes in protein patterns have been mentioned to date (17,21

Plant Water-Stress Response Mechanisms

“…Dasgupta and Bewley (1984) [107] pointed out water stress reduced protein synthesis in all regions of barley leaf. Vartanian et al, (1987) [108] mentioned the presence of drought specific proteins in tap root in Brassica. Dasgupta and Bewley (1984) [107] pointed out water stress reduced protein synthesis in all regions of barley leaf.…”

“…For instance, free proline accumulation in response to drought in many plant species tissues is well documented [111][112][113][114][115]. Vartanian et al, (1987) [108] mentioned the presence of drought specific proteins in tap root of Brassica.…”

Stress hydrique: étude des mécanismes moléculaires et des modifications de l'expression du génome

“…Les ARNm qui s'accumulent plus tardivement seraient induits par l'ABA (Guy, 1990 ;Ho et Mihkind, 1991). Les polypeptides de Mm similaires à ceux détectés chez la Tomate s'accumulent chez d'autres espèces, en réponse aux stress hydriques (Gomez et al, 1988 ;Vartanian et al, 1987) ou aux stress salins (Mundy et Chua, 1988 ;Ramagopal, 1987 ;Ramagopal et Carr, 1991). A la suite d'un stress hydrique, des protéines riches en glycine s'accumulent dans les feuilles (Gomez e al., 1988 ;Ho et Mishkind, 1991 ;Mundy et Chua, 1988), les racines (Mundy et Chua, 1988) et les embryons (Baker et al, 1988 ;Dure et al, 1989 ;Gomez al., 1988).…”

Differential Two-Dimensional Protein Patterns as Related to Tissue Specificity and Water Conditions in Brassica napus var oleifera Root System

“…It involves de novo formation of short, tuberized and hair-deprived roots which, due to their high desiccation tolerance and ability to resume growth rapidly upon rehydration, represent a survival potential at the root level (24). In a short communication (25), we previously reported notable and reversible changes in two-dimensional protein patterns of Brassica napus var oleifera tap root under drought. Most polypeptides appearing under drought were also found in the drought-induced short roots.…”

“…Rehydration which induces elongation of these organs makes their protein pattern very similar to that of the well-watered lateral roots. (25) under different moisture regimes. Young 48 h germinating seedlings were planted in a sandy soil initially watered at field capacity.…”