Epigenetics and transgenerational memory in plants under heat stress

The concept that plants are cognitive and intelligent organisms capable of learning and retaining memory may sound alien to most plant scientists mainly because of the paucity of literature in the subject and also due to the complexity of the subject. Plants are sessile organisms and so have intricate physiological, biochemical and molecular mechanisms by which they react to abiotic stress and it is possible that epigenetics has an important role in response to stress stimuli in plants. Heat stress is a consequence of the changing climate now and can affect plant growth and productivity in agriculture crops. Heat stress induced epigenetic modifications caused by DNA methylation, histone restructuring, chromatin remodeling is known to induct memory in plants that can be retained in future generations to counter heat stress effectively. Expression of genes to a large extant are influenced by the chromatin environment and there are states of chromatin dynamics that can dictate the specific genes that are stress responsive for resultant adaptation to heat stress. In this minireview we will discuss on transgenerational memory and the regulation of responses to heat by epigenetic modifications such as DNA methylation, modifications and variations in histones and histone chaperones, chromatin remodeling, small RNA and long noncoding RNAs.