**2.6 ER and mitochondria**

Considering the relationship between the endoplasmic reticulum and mitochondria, there is a membrane that provides the connection between the ER and the mitochondria [30]. This membrane has been named the mitochondria-associated ER membrane (MAM). Communication between the ER and the mitochondria is provided by this membrane. This communication is very important for the survival of the cell. Many functions such as lipid transfer, autophagosome formation, mitochondrial fission, Ca2+ homeostasis, and apoptosis are regulated by this communication [33]. In this contact zone, calcium influx occurs into the intermembrane space and the mitochondrial matrix. It has been stated that changes in Ca2+ levels occur in case of disturbance in the regulation of this flow, thus affecting apoptosis, mitochondrial division, and motility, and altering the activity of mitochondrial Ca2+ binding proteins [34]. As a result, ER and mitochondrial communication disorders lead to a number of problems such as mitochondrial damage, Ca2+ dyshomeostasis, ER stress,

*The Relationship of Some Neurodegenerative Diseases with Endoplasmic Reticulum Stress… DOI: http://dx.doi.org/10.5772/intechopen.111693*

defects in lipid metabolism, autophagy, decreased respiratory chain activity, and oxidative phosphorylation [35]. It has been determined that the communication disorder between these two organelles plays an important role in the regulation of neurological activity. It has been determined that the relationship between these organs is impaired in Alzheimer's, Parkinson's, and Huntington's disease [36].
