Figure 6.

Positive feedback loop between XAL2 gene transcription and auxin distribution. Auxin upregulates XAL2 gene transcription and this MADS regulates efflux auxin carriers controlling auxin distribution/participation in the proliferation of the root meristematic cells. It is shown that while the response to auxin of PIN4 is mediated by XAL2, the auxin response of PIN1 does not depend on XAL2. Red arrows indicate transcript regulation based on the experimental data and green arrow indicates proteins involved in auxin distribution.