Table II.

E3-E2 specificity as determined by in vitro ubiquitination assays

Each E3 or GST-RING protein was tested in in vitro ubiquitination assays with a number of Arabidopsis E2s from different subfamilies as described and defined by Stone et al. (2005). Protein ubiquitination was observed (+) for a number of E2-E3 combinations. Two instances occurred where activity was inconsistent (±). For other E2-E3 combinations, protein ubiquitination was not detected (−). E2-E3 combinations that were not determined (nd) are indicated.

E3RING TypeE2 (UBC)
8101128293019343536
At1g02860HCa
At1g12760H2+++++
At1g14260v++++
At1g18760D++++
At1g22500H2+++++
At1g50440v+++±
At1g61620HCa
At1g63900HCa+++++
At1g65430HCb+++
At1g68180H2+++++nd
At1g74410H2
At2g18670H2
At2g22690S/T
At2g28530C2++nd
At2g28840HCa
At2g42360H2++++++++
At2g44330H2++++++
At2g47700H2+++++++
At3g05250HCa++++
At3g05545H2+±+
At3g06330v+++++
At3g09760v+++nd
At3g29270HCa+++++
At3g45555HCbnd
At3g47160HCa+++
At3g48070C2+++nd
At4g10160H2++++nd
At4g14220H2+++++++
At4g27470HCa+++++
At5g20910H2++++++
At5g37270H2+++++++
At5g38070v+++
At5g42200H2+++++
At5g53910D+++nd