Neural functions of small heat shock proteins

Abstract

Stress response is a cellular widespread mechanism encoded by a common protein program composed by multiple cellular factors that converge in a defense reaction to protect the cell against damage. Among many mechanisms described, heat shock proteins were proposed as universally conserved protective factors in the stress core proteome, coping with different stress stimuli through its canonical role in protein homeostasis. However, emerging evidences reveal non-canonical roles of heat shock proteins relevant for physiological and pathological conditions. Here, we review the implications of inducible heat shock proteins in the central nervous system physiology. In particular, we discuss the relevance of heat shock proteins in the maintenance of synapses, as a balanced protective mechanism in central nervous system development, pathological conditions and aging.

Keywords: aging; central nervous system; chaperones; environment; neuroprotection; pathology; stress; synapses.

Figure 1

Neural functions of chaperones. Neurons sense environmental stress and internal signals, and react through heat shock proteins (HSPs) function. HSPs functions in the nervous system regulate neuronal physiology.

Figure 2

Diagram of small chaperones sHSP23, sHSP26 and Pkm mechanisms of function. sHSP23 (blue) and sHSP26 (green) accumulate in neuronal cytoplasm. Pkm Kinase protein (yellow) promotes the inhibition of sHsp23 transcription. In consequence, sHSP23/26 complex modulates synapse number and neuronal activity. sHSP: Small heat shock protein.