MCD BIO C141 Lecture Notes - Lecture 7: Histidine Kinase, Agrobacterium Tumefaciens, Cytokinin

14 views9 pages

Document Summary

Cytokinin: a class of plant growth substances that promote cell division, or cytokinesis, in plant roots and shoots. They are involved primarily in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and leaf senescence. Ipt gene: expression of ipt, a cytokinin biosynthetic gene from agrobacterium tumefaciens, under the control of the promoter from a senescence-associated gene (sag12) has been one approach used to delay senescence [10]. Arabidopsis histidine kinase (ahk): functions as an osmosensor histidine kinase that detects water stress and transmits the stress signal to a downstream mapk cascade. This protein undergoes an atp- dependent autophosphorylation at a conserved histidine residue in the kinase core, and a phosphoryl group is then transferred to a conserved aspartate residue in the receiver domain. Positive regulator of drought and salt stress responses, and abscisic acid (aba) signaling. Confers drought tolerance, probably by regulating levels of aba accumulation. Plays a redundant role in regulating plant growth and development.