Auxin biosynthesis: spatial regulation and adaptation to stress 

 -  Journal of Experimental botany, https://doi.org/10.1093/jxb/erz283, 2019 .
<br/><br/> The plant hormone auxin is essential for plant growth and development, controlling both organ development and overall plant architecture. Auxin homeostasis is regulated by coordination of biosynthesis, transport, conjugation, sequestration/storage, and catabolism to optimize concentration-dependent growth responses and adaptive responses to temperature, water stress, herbivory and pathogens. At present, the best defined pathway of auxin biosynthesis is the TAA/YUC route, in which the tryptophan aminotransferases TAA and TAR and YUCCA flavin-dependent monooxygenases produce the auxin indole-3-acetic acid from tryptophan. This review highlights recent advances in our knowledge of TAA/YUC-dependent auxin biosynthesis focussing on membrane localisation of auxin biosynthetic enzymes, differential regulation in root and shoot tissue, and auxin biosynthesis during abiotic stress. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>AUXIN BIOSYNTHESIS<br/>MEMBRANE<br/>ENDOPLASMIC RETICULUM<br/>YUC<br/>TAA<br/>TAR<br/>HALOTROPISM<br/>METABOLON<br/>HEAT STRESS<br/>DROUGHT