Table 1.

Astrocytes express five types of IF proteins. GFAP and vimentin isoforms are splice variants of a single gene and lamin isoforms are encoded by different genes.

IF Protein	Type	Isoforms in Astrocytes	Size (kDa)	Function in Astrocytes
Glial fibrillary acidic protein (GFAP)	III	α, β, γ, δ (ε), ξ, κ, Δ135, Δ164, Δexon6, Δexon7 [18,37]	38–50 [38]	Resistance to mechanical stress, cell migration and motility, mitosis, myelinization, maintenance and permeability of the blood–brain barrier, neurogenesis, chaperone-mediated autophagy, vesicle mobility, glial scar formation, response to hypoosmotic stress [12,13,32,37,41,42,43,44,45]
Vimentin	III	No splice variants reported in astrocytes	57 [46]	Mechanical integrity of cells and tissues, neurogenesis, glial scar formation, vesicle trafficking, cell morphology, cell motility, cell division, response to hypoosmotic stress [12,13,41,43,44,45,47,48,49]
Nestin	VI	No splice variants reported in astrocytes	240 [50]	Shape of protrusions, neurogenesis, cell motility [44,51]
Synemin	VI	α, β (human), H, M, L (mouse)	230 [52], 180 H (α),150 M (β), 41 L [53,54]	Astrocytoma motility [55]
Lamin	V	A, B1, B2, C	60–70 kDa [56]	Control of gene expression [57], transport of neurofibromin to the nucleus [58], nucleocytoplasmic transport [59]