The present invention relates to nucleic acid and amino acid sequences that confer herbicide resistance in plants, as well as herbicide resistance in plants, plant seeds, plant tissues and plant cells comprising such sequences. In a preferred embodiment, the sequences of the present invention confer a tolerant phenotype in plants in response to a chronic and/or acute inhibitin dose of auxinic herbicides. The present invention also provides homologous sequences with a high degree of functional similarity.