Extended Data Figure 6: Characterization of miPEP165a from A. thaliana.

a, miPEP165a sequence: the 5′ part of the pri-miR165a, as identified in ref. 7. The miPEP165a-coding sequence is in blue, the miR165a* in green, and the mature miR165a in red. The putative alternative start codons are in light blue, the ATG start codon of the miPEP165a is underlined, and the amino acid sequence of the miPEP165a is shown below. The black vertical line indicates the 5′ end of the pre-miR165a precursor (http://www.mirbase.org). b–f, Expression of the miPEP165a in A. thaliana roots. b, c, Confocal fluorescence microscopy of A. thaliana root tips showing expression of a GUS-GFP fusion gene fused to the first ATG of the sequence encoding the pri-miR165a under the control of 4 kb of the promoter (green), and the corresponding bright-field image. The red fluorescence is due to the constitutively expressed DsRed fluorescent protein. d, A root tip as in (b, c) showing staining for GUS activity (blue) due to expression of the GUS-GFP fusion gene. e, f, Absence of staining for GUS activity in root tips transformed with expression vectors encoding GUS fusion genes fused to the first GTG (e) or CTG (f) of the pri-miR165a-coding sequence under the control of 4 kb of the promoter (scale bars, 100 μm). g, Main root length of seedlings treated with water (control) or with various concentrations of synthetic miPEP165a dissolved in water. Error bars represent s.e.m., asterisks indicate a significant difference between the treatment and the control according to Student’s t-test (n = 100 independent plants, P < 0.05).