R. Scott Poethig is the John H. and Margaret B. Fassitt Professor of Biology at the University of Pennsylvania. He received his Ph.D. from Yale University in 1981, and did post-doctoral research at Stanford University and the University of Missouri from 1981-1983. He has been on the faculty of the U. of Pennsylvania since 1983. Dr. Poethig is a developmental geneticist, whose primary interest is shoot developmental in plants. Among other things, he has studied the cellular basis of leaf development, the origin of the shoot apical meristem during embryogenesis, and the regulation, function and evolution of the juvenile-to-adult vegetative transition in plants. His most significant contribution is the discovery of the molecular mechanism of this developmental transition. Dr. Poethig has also worked on the biogenesis and function of miRNAs and other endogenous small RNAs, including trans-acting siRNAs, which his laboratory discovered.

Research Interests

We are currently working on the relationship between vegetative phase change (i.e. the juvenile-to-adult vegetative transition) and reproductive phase change (i.e. the acquisition of reproductive competence). It is generally assumed that vegetative phase change is a pre-requisite for reproductive competence, but there is no conclusive evidence for this, and there are many species in which this is not the case. In addition, we are characterizing natural variation in vegetative phase change in Arabidopsis and species within the Acaceae, and identifying genes responsible for this variation. Finally, we are working to determine the ecological significance of vegetative phase change?why do plants make juvenile and adult leaves?

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Primary Section

Section 25: Plant Biology

Secondary Section

Section 22: Cellular and Developmental Biology