The Searle Scholars Program has awarded a $300,000 research grant to Upasna Sharma, assistant professor of molecular, cell, and developmental biology at UC Santa Cruz. Sharma, who studies the mechanisms behind “epigenetic” inheritance, is one of 15 young scientists to receive the prestigious award this year.
The Searle Scholars Program makes grants to selected universities and research centers to support the independent research of exceptional young faculty in the biomedical sciences and chemistry. The program supports high-risk, high-reward research across a broad range of scientific disciplines.
Sharma’s research focuses on the process by which the effects of environmental stresses can be transmitted from one generation to the next. Several lines of evidence suggest, for example, that a father's diet or experience of famine can affect the health and longevity of his children and grandchildren. These effects are not the result of mutations or other genetic changes to the DNA passed down in the chromosomes, but are thought to be mediated by “epigenetic” factors that change how genes are expressed.
“Although there is mounting evidence from worms to humans suggesting that the parent’s environment can influence their offspring, the mechanism of such intergenerational inheritance remains deeply mysterious,” said Sharma, who received the NIH Director’s New Innovator Award from the National Institutes of Health in 2019.
Sharma’s previous work made significant advances in understanding intergenerational epigenetic inheritance. She showed that epigenetic information related to the father's diet is transmitted to offspring via sperm, and that the carriers of this epigenetic information are small RNA molecules that are produced by the cells of the epididymis, the tubule in which sperm mature after leaving the testes. This research provided the first direct evidence of RNA-mediated communication between non-reproductive body cells (called somatic cells) and the germ cells (sperm).
“These astonishing observations provide a focus for my current research, which aims to elucidate the mechanism of RNA-mediated soma-germline communication, and its consequences to offspring health,” Sharma said.
Over the next few years, her lab will examine the biogenesis of small RNAs in mammalian sperm and investigate how exposure of an organism to various environmental conditions alters or reprograms the small RNA payload of its sperm to affect its offspring.
