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suraj P. Bhat, PhD
Associate Professor of Ophthalmology
Member of the Jules Stein Eye Institute
Member of the Molecular Biology Institute
ReseaRch summaRy
Molecular Biology of Vision
Dr. Bhat’s laboratory studies the regulation of gene
activity during differentiation and development of the
vertebrate eye. This involves isolation and characterization
of genes and gene products, identification of the
regulatory elements and factors, and elucidation of their
mechanisms employing both in vivo and in vitro paradigms
with manipulated gene sequences.
Two areas of research currently under investigation
are focused on gaining deeper insight into molecular
mechanisms that developmentally predispose the eye to
visual impairment through ocular lens pathologies such
as cataracts, and through retinal diseases including
age-related macular degeneration (AMD).
One area of attention is the study of the developmental
and tissue-specific control of the heat shock promoter
of the αB-crystallin gene and its involvement in cataractogenesis.
Another is the elucidation of the physiological
function of the αB-crystallin protein in the ocular
lens, in the neuroretina and retinal pigment epithelium
(RPE), and in the brain. Technically this work involves
gene manipulations and the study of their consequences
on the phenotype, both in vitro (cultured cells) as well as
in vivo (transgenic animals).
Studies on the regulation of the expression of the small
heat shock protein gene, αB-crystallin are focused
on heat-shock transcription factor 4 (HSF4), which
Dr. Bhat’s laboratory has reported to be the predominant
heat shock transcription factor of the developing
ocular lens and whose post-natal expression correlates
with the most prevalent form of early childhood lamellar
cataracts. Dr. Bhat’s laboratory has generated mouse
models of this cataract, thus enabling first-time investigation
of this childhood pathology.
Studies on the function of the αB-crystallin protein in
the lens and the RPE (in particular its relation to AMD)
are focused on elucidating its “noncrystallin” function,
which is relevant both in the transparent and nontransparent
physiology. These investigations in Dr. Bhat’s
laboratory have led to the discovery of the secretion
of αB-crystallin from the RPE in lipoprotein vesicles
known as exosomes, and initiated studies on
elucidation of intercellular communication (via
exosomes) in the RPE, in health, and in disease.
Public Service
Member, Joint Working Group INDO-US Collaboration in
Vision Research
Assessor, National Health and Medical Research Council,
Australia
Editor, Molecular Vision
Editorial Board Member, Developmental Neuroscience
Editorial Board Member, International Journal of Biochemistry
and Molecular Biology, e-Century Publishing Corporation, USA
Reviewer for many scientific journals
Faculty | Bhat 29