sentence: Given the correlation of APY suppression and treatment with ATP with growth inhibition [ 26,63 ] and disrupted auxin transport [ 64 ] , it would be of significant interest to examine whether the levels of APY expression and RRTF1 expression are inversely correlated specifically in root tips.Evidence that could favor a link between the expression of APY and RRTF1 in controlling root growth would include the fact both APY suppression and increased RRTF1 expression inhibit root growth .