The eect of the anti-microtubular drug Oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide) on growth and elongation of rice ( Oryza sativa L. cv. Arborio) roots and coleoptiles was investigated. At 100 nM, Oryzalin strongly reduced primary root elon- gation, caused loss of cell anisotropy and the disappear- ance of the cortical microtubule array. Under these conditions the amounts of a - and b -tubulin protein, but not mRNA, were heavily reduced. Similar data were also obtained in coleoptile segments treated with dierent concentrations of Oryzalin. However, when coleoptile elongation was inhibited by cis -abscisic acid, remarkable decreases in a -and b -tubulin accumulation were ob- served to occur at the mRNA level but not at the protein level. The transcriptional decreases could be reversed by re-addition of 3-indole acetic acid. Altogether, these data indicate that rice tubulin accumulation can be controlled at dierent levels, mRNA or protein, in response to Oryzalin or abscisic acid treatments.
In rice, Oryzalin and abscisic acid di erentially a ect tubulin mRNA and protein levels
Silvia Gian;Diego Breviario
1998
Abstract
The eect of the anti-microtubular drug Oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide) on growth and elongation of rice ( Oryza sativa L. cv. Arborio) roots and coleoptiles was investigated. At 100 nM, Oryzalin strongly reduced primary root elon- gation, caused loss of cell anisotropy and the disappear- ance of the cortical microtubule array. Under these conditions the amounts of a - and b -tubulin protein, but not mRNA, were heavily reduced. Similar data were also obtained in coleoptile segments treated with dierent concentrations of Oryzalin. However, when coleoptile elongation was inhibited by cis -abscisic acid, remarkable decreases in a -and b -tubulin accumulation were ob- served to occur at the mRNA level but not at the protein level. The transcriptional decreases could be reversed by re-addition of 3-indole acetic acid. Altogether, these data indicate that rice tubulin accumulation can be controlled at dierent levels, mRNA or protein, in response to Oryzalin or abscisic acid treatments.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
