The focus of the Muscle Research Group is on the dynamic calcium signalling in skeletal and cardiac muscle that regulates contraction.  My particular interest is in the complex regulation of the ryanodine receptor calcium release channel which releases the Ca²⁺ ions required for contraction during excitation-contraction coupling.  Many myopathies are linked to mutations in the ryanodine receptor or in its associated regulatory proteins which alter its ion channel function and lead to disorders such as malignant hyperthermia, central core disease and myotonic dystrophy in skeletal muscle or cause arrhythmias in the heart that can lead to sudden death.  Our aims are (a) to understand how myopathy-associated mutations alter the function of ryanodine receptor channels to lead to muscle weakness and (b) to understand the interactions between the surface membrane dihydropyridine receptor and ryanodine receptor that enables excitation-contraction coupling in skeletal muscle.

Dulhunty graduated from The University of Sydney, Australia, in 1969 with a Bachelor of Science degree and Honours in Physiology.  She obtained a PhD from the University of NSW in 1973 presenting a thesis describing muscle electrophysiology studies carried out with Professor Peter Gage.  She was then awarded a Muscular Dystrophy Postdoctoral Fellowship to work at the University of Rochester (NY) with Professors Paul Horowicz, Clara Franzini-Armstrong and Camillo Peracchia.  She returned to Australia in 1975 and established a Muscle Research Laboratory in the Department of Anatomy at The University of Sydney. In 1982 Dulhunty, with Professors Peter Gage and Peter Parry, was awarded and a Centre of Excellence for Nerve Muscle Research at the University of NSW.  The Centre moved to the Australian National University in Canberra in 1984, where Dulhunty re-established the Muscle Research Laboratory.  She was awarded a DSc degree by the University of NSW in 1988 for her extensive research into muscle excitation-contraction coupling (ECC).  Dulhunty was appointed to an Emeritus position at the ANU in 2017. In 2022, she was awarded an AM (Australian Medal) for contributions to Medical Research and Student training

Dulhunty’s research has focussed on the translation of electrical signals in the surface membrane of muscle fibres into the release of the calcium ions from their internal in the sarcoplasmic reticulum (SR), to enable muscle contraction in the process of excitation contraction coupling (ECC).  In her PhD studies she explored the complex nature of transverse (T-) tubule extensions of the surface membrane which conduct the surface electrical signal throughout the fibre cross-section.  The discovery of asymmetric charge movement arising from dihydropyridine receptors in T-tubules allowed her to examine this voltage sensor for ECC in fast and slow-twitch mammalian muscle and to apply this to her subsequent studies of the voltage dependence for ECC.  The other major component of ECC, the ryanodine receptor (RyR) calcium release channel in the SR, was identified in the late 1980s.  Dulhunty was amongst the first researchers to study single RyR ion channels from skeletal and cardiac muscle using lipid bilayer electrophysiology.  She has continued to study RyR channels, combining electrophysiology, biochemistry, protein chemistry, structural biology and molecular biology to explore normal RyR function and pathological changes that reduce skeletal muscle function and which can compromise cardiac muscle to the extent of causing heart attack.