Altering Asr1 gene expression has dramatic effects on metabolism in different plant species

FRANKEL N; BALBO I; MAZUCH J; IUSEM N; FERNIE AR; CARRARI F

Iguazú, Misiones, Argentina

Congreso; XL Reunión anual de la Sociedad Argentina de Investigaciones en Bioquímica y Biología Molecular (SAIB); 2004

The Asr gene family was first cloned from commercial tomato.Since then it has been found widely spread throughout the plantkingdom with the exception of Arabidopsis. Four members havebeen found in tomato localised on chromosome IV. Asr genes havebeen shown to be regulated by various kinds of stresses and ABA.On the basis of in vitro experiments a recent report hasdemonstrated that ASR1 binds DNA in a Zn-dependent manner;in addition another report remarks that an ASR acts as atranscriptional regulator of a hexose transporter in grape. However,the physiological role of these proteins remains to be elucidated.Here we present results with tobacco and potato plants that expresstomato Asr1 either in sense or antisense orientation. By means ofa detailed metabolic analysis we have observed dramatic effectson growth and hexose metabolism, with phenotypes resemblingthose of plants displaying altered sugar transport. These featuressupport a potential role for this transcription factor as a centralcontributor to a mechanism for sensing and/or distributing sugarwithin the plant.