Raúl Padrón, a Professor at the University of Massachusetts Chan Medical School since 2018, is a structural biologist recognized for his work on the structure and function of myosin thick filaments of skeletal, cardiac, and smooth muscle. He is known particularly for his studies on the myosin interacting-head motif (IHM) structure and function and their implications on how the thick filaments of muscle relax, super-relax, and become activated, and its consequences on the molecular pathogenesis of human muscle diseases hypertrophic and dilated cardiomyopathy. Padrón was born and grew up in Caracas, Venezuela. He graduated from the Universidad Central de Venezuela with a degree in Electrical Engineering and from the Venezuelan Institute for Scientific Research with an M. Sc. in Biology and a summa cum laude Ph.D. in Biophysics and Physiology in 1979. He was a postdoctoral fellow in muscle structure and function at the MRC Laboratory of Molecular Biology (Cambridge, U.K.) in 1980. He joined the Venezuelan Institute for Scientific Research in 1983, where he founded the Center of Structural Biology, where he was an International Research Scholar at the Howard Hughes Medical Institute (HHMI) from 1997 until 2011. He was elected a member of the Latin American Academy of Sciences (ACAL) in 2002, a fellow of the World Academy of Sciences (TWAS) in 2004, and an international member of the U. S. National Academy of Sciences in 2018.

Research Interests

Raúl Padrón's research focuses on the structure, function, and evolution of the myosin interacting-heads motif (IHM) and its implications on human disease. The IHM is established by the interactions of the two (blocked and free) heads of the myosin molecule and its myosin tail subfragment-2, forming an asymmetric arrangement that, in the relaxed state, inhibits the ATPases of both heads. The IHM is conserved since before animals emerged, independently of the muscle type (striated, cardiac, or smooth) or in non-muscle cells, showing its fundamental importance as the structural basis underlying relaxation through both heads ATPase inhibition, implying ATP energy-saving via a super-relaxation mechanism. Padrón's current focus is on (1) the study by single-particle cryo-EM of the near-atomic structure and function of the IHM from skeletal, smooth, and cardiac muscle and non-muscle cells and of the IHM on thick filaments of invertebrate skeletal and vertebrate skeletal and cardiac muscle; aiming to understand the consequences of mutations and therapeutic drugs involving the IHM on myosin, essential and regulatory myosin light chains, MyBP-C and titin on human diseases like hypertrophic and dilated cardiomyopathy; and (2) the study by time-resolved X-ray diffraction of the structure, function and impact of therapeutic drugs on the blocked and free heads of the IHM in live relaxed and contracting cardiac and skeletal muscle.

Membership Type

International Member

Election Year


Primary Section

Section 42: Medical Physiology and Metabolism

Secondary Section

Section 29: Biophysics and Computational Biology