Chapter 18 - The Multifaceted Roles of miR156-targeted SPL Transcription Factors in Plant Developmental Transitions

Abstract

Plants undergo a series of developmental transitions during their life cycles. After seed germination, plants pass through two distinct phases: a vegetative phase in which leaves are produced, and a reproductive phase in which flowering occurs. The vegetative phase can be further divided into juvenile and adult phases, based on reproductive competence and morphological changes. Growing lines of evidence indicate that microRNA156 (miR156) and its target SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors exert an evolutionarily conserved role in regulating developmental transitions in plants. This chapter reviews advances in our understanding of the molecular basis by which age regulates miR156 expression, and the role played by miR156-targeted SPL transcription factors in developmental transitions as well as other processes that require proper timing.