Apical meristem exhaustion during determinate primary root growth in the moots koom 1 mutant of Arabidopsis thaliana
Por:
Hernandez-Barrera, A, Ugartechea-Chirino, Y, Shishkova, S, Napsucialy-Mendivil, S, Soukup, A, Reyes-Hernandez, BJ, Lira-Ruan, V, Dong, GF, Dubrovsky, JG
Publicada:
1 dic 2011
Resumen:
An indeterminate developmental program allows plant organs to grow continuously by maintaining functional meristems over time. The molecular mechanisms involved in the maintenance of the root apical meristem are not completely understood. We have identified a new Arabidopsis thaliana mutant named moots koom 1 (mko1) that showed complete root apical meristem exhaustion of the primary root by 9 days post-germination. MKO1 is essential for maintenance of root cell proliferation. In the mutant, cell division is uncoupled from cell growth in the region corresponding to the root apical meristem. We established the sequence of cellular events that lead to meristem exhaustion in this mutant. Interestingly, the SCR and WOX5 promoters were active in the mko1 quiescent center at all developmental stages. However, during meristem exhaustion, the mutant root tip showed defects in starch accumulation in the columella and changes in auxin response pattern. Therefore, contrary to many described mutant
Filiaciones:
Univ Nacl Autonoma Mexico, Dept Biol Mol Plantas, Inst Biotecnol, Cuernavaca 62250, Morelos, Mexico
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