Hiyaa Ghosh

Biography

Hiyaa Ghosh is a researcher in the department of Neurobiology from the National Centre for Biological Sciences.

Research Interest

They are interested in understanding specific cellular processes in the adult brain that are highly relevant both in the steady state and during pathogenesis. To this end, we exploit the power of mouse genetics for specific spatial and temporal deletion of gene, followed by morphometric, molecular and biochemical analysis. Unlike during development and in the early years of life, much of the adult nervous system is thought to be post-mitotic structure, incapable of generation or regeneration. However, there are two specific regions in the adult brain, the subventricular zone (SVZ) of the lateral ventricles, and the subgranular zone (SGZ) of the dentate gyrus in the hippocampus, where new neurons are constantly generated throughout adulthood by a process known as adult neurogenesis. Hippocampal (SGZ) neurogenesis has been associated with learning and memory, and not surprisingly, has been implicated in various neurodegenerative and psychiatric disorders. We are interested in understanding the molecular regulators of neural differentiation and maturation during hippocampal neurogenesis. An essential component of neuronal function is the network of dendritic structures, called dendrite arbor, and their sub-structures, dendritic spines. Dendrites carry the electrical inputs from transmitting cells to the dendrite-projecting cell body. The reception of incoming electrical stimulation happens at multiple synapse points throughout the dendritic tree. Thus, the arbor-like structural layout of dendrites increases the surface area for reception of the electrochemical signal. Changes in dendritic structures, are an integral component of brain plasticity, where most of the plasticity is manifested by the dendritic spines. However, certain neurons in the adult brain, such as the hippocampal CA1 neurons, have been shown to be plastic in their dendritic branches as well. The importance of the structural integrity of the dendritic arbors is reflected by findings that have correlated defective dendrite structures to multiple neurodegenerative and psychiatric diseases. Many of these diseases are late onset diseases suggesting a deterioration of normal dendritic arbors. Interestingly, while much has been explored about how dendrites are formed, very little is known about how the already formed dendritic arbors are proactively maintained throughout the adult lifespan.We are interested in understanding the structural regulation and maintenance of dendrite structures in the adult brain. Although considered as an immune-privileged organ, the adult brain actually has access to various immune cell types, including its resident microglia, and the hematopoietic immune cells that are accessed through its perivascular spaces. Recent studies suggest a role for the immune cells, both resident and hematopoietic, on various cellular processes in the adult brain, including adult neurogenesis. We are interested in understanding these neuro-immune interactions at the molecular level by investigating the various participant immune cell types.