Phase 2 (plateau), calcium channels open and fast potassium channels close

TLS Online TPP Program

#Id: 8578

#Unit 2. Cellular Organization

Type IV Ifs consist of the three related subunits

NF-L, NF-M, and NF-H that make up the neurofilaments found in the axons of neurons

TLS Online TPP Program

#Id: 8579

#Unit 2. Cellular Organization

Amyotrophic lateral sclerosis (ALS, or Lou Gehrig’s disease) 

neurodegenerative disease 

associated with an accumulation and abnormal assembly

of neurofilaments in motor neuron cell bodies and in the axon

TLS Online TPP Program

#Id: 8580

#Unit 2. Cellular Organization

In humans, three genes encode lamins: 

Lamins A and C (alternatively spliced gene) 

Lamins B1 and B2

TLS Online TPP Program

#Id: 8581

#Unit 2. Cellular Organization

B-type lamins - expressed in essentially all cells (primordial lamin proteins)

lamins A and C - developmentally regulated

TLS Online TPP Program

#Id: 8582

#Unit 2. Cellular Organization

Lamins B are post-translationally prenylated, which helps them associate with the inner nuclear envelope membrane.

TLS Online TPP Program

#Id: 8583

#Unit 2. Cellular Organization

Lamins 

contribute to genome organization as well as to the rigidity of the nucleus through linkages to the

cytoskeleton involving proteins with SUN and KASH domains