Muscle cells have an abundant, modified smooth ER called the sarcoplasmic reticulum.

The release and reuptake of Ca2+ by the sarcoplasmic reticulum trigger myofibril contraction and relaxation, respectively

TLS Online TPP Program

#Id: 8528

#Section 3: Genetics, Cellular and Molecular Biology

Polyglutamylation has a key role in the beating of cilia and flagella

TLS Online TPP Program

#Id: 8527

#Section 3: Genetics, Cellular and Molecular Biology

Kinesin-1 associates preferentially with detyrosylated and acetylated microtubules.

TLS Online TPP Program

#Id: 8526

#Section 3: Genetics, Cellular and Molecular Biology

Polyglutamylation and polyglycylation are likely mutually exclusive, so they would not normally occur at the same time & both can enhance microtubule stability,

TLS Online TPP Program

#Id: 8525

#Section 3: Genetics, Cellular and Molecular Biology

Detyrosylated microtubules are more stable, because they are more resistant to depolymerization by kinesin-13 and related proteins.

TLS Online TPP Program

#Id: 8524

#Section 3: Genetics, Cellular and Molecular Biology

Detyrosylation 

tyrosine can be removed by a carboxypeptidase, where it sequentially removes the C-terminal tyrosines from α-tubulin subunits. 

TLS Online TPP Program

#Id: 8523

#Section 3: Genetics, Cellular and Molecular Biology