Final answer:
Microtubule-associated proteins are controlled by post-translational modifications such as phosphorylation. When MAP-T in neurons is hyper-phosphorylated, it can lead to the disassembly of microtubules and the formation of neurofibrillary tangles. Other PTMs include acetylation and ubiquitination, which also play roles in protein stability and cellular dynamics.
Step-by-step explanation:
Microtubule-associated proteins (MAPs) are regulated by post-translational modifications (PTMs) of specific amino acids. One common PTM that controls MAPs is phosphorylation. In neurons, a Microtubule-Associated Protein Tau (MAP-T) can become hyper-phosphorylated, changing its conformation. This modification causes microtubules to disassemble and the malformed tau proteins to form neurofibrillary tangles, which are implicated in neurodegenerative disorders.
Apart from phosphorylation, other PTMs such as acetylation of the N-terminal amino acid and ubiquitination related to amino acids at the N-terminal end can impact the stability and function of proteins, including MAPs. These modifications are critical in regulating various functions such as protein degradation, cell motility, and the determination of cell shape.
These intricate cellular mechanisms underscore the importance of specific amino acid modifications in the dynamic regulation of cytoskeletal structures.