Study uncovers memory molecules in plants

An Indian biologist has discovered the existence of special proteins, called prions, in plants. Earlier found in yeast, insects, and mammals, this protein could explain the decades-old mystery of how even plants formed memories.

Sohini Chakrabortee, who spent three years scanning over 20,000 proteins in plants from the mustard family, had identified at least one protein that behaved like a prion and was capable of building molecular memories, such as those of exposure to a prolonged period of cold that preceded flowering.

Prions, a unique class of proteins, are capable of altering their shapes, self-propagate by inducing other molecules of same protein to adopt their shapes, and cluster together. While prions had, in the early-1980s, been identified as having a role in the transmission of certain neurodegenerative brain disorders, studies in fruit-flies and mice over the past five years had suggested that prion-like proteins might be essential in maintaining long-term memories in these organisms.

"This is the first evidence that a plant protein may self-replicate as a prion - this opens up the possibility of protein-based memories in plants," said Chakrabortee, who led the research as a post-doctoral fellow in the laboratory of Susan Lindquist at the Whitehead Institute for Biomedical Research at the Massachusetts Institute of Technology in the US, The Telegraph reported.

Brain cells in humans store information by rearrangement of molecules in a special configuration. Similarly, prions present in plants could also change their shape in such a way to memorise things.

Several studies in the past had also shown that prions were capable of storing information for a long duration of time. The present study detailed in the proceedings of the National Academies of Sciences attempts to explain the role of prions of plants. Prions also played a crucial role in the flowering of plants.