Fig 1. Loss of CEP2 function results in shortened primary roots.

Residual CEP2 activity in CEP2 knock down plants results in longer roots as compared to cep2 knock out plants, but shorter as compared to WT. (A) Primary root length in seven days old seedlings of homozygous cep1 ko, cep2 ko and of cep1 cep2 double ko/kd mutants (cep1+cep2-RNAi) versus Col-0 WT plants. cep2 ko mutants exhibited shorter primary roots compared to Col-0 WT plants. Loss of CEP1 has no influence on primary root length. Residual CEP2 activity (0.5–2% compared to WT) in cep1 cep2 double ko/kd plants resulted in primary roots significantly longer than cep2 ko mutants but shorter than WT plants. Root length is shown in cm. (B) Comparison of primary root length in 5, 7 and 11 days old seedlings of homozygous cep2 ko plants and cep1 cep2 double ko/kd mutants (cep1+cep2-RNAi) with a residual CEP2 activity of 0.5% (line 2.21) and 2% (line 3.14) as compared to WT (100% activity). Columns marked with different letters indicate statistically different groups according to the ANOVA-and Duncan test (p<0.001). (C) Primary root length expressed as percentage of WT plants. Data represent the respective means of two independent experiments (biological replica) each comprising 120 plants per line.