Question

Which of the following cytoskeletal proteins is needed for cell-to-cell attachments (in anchoring junctions or desmosomes), but is not required for either external or internal cell movements?

A. alpha-tubulin (a microtubule protein) B. keratin (an intermediate filament protein) C. actin (a microfilament protein) D. beta-tubulin (a microtubule protein) E. all of the above

Answer 1

B)Keratin (an intermediate filament)

Keratin is protein present in cell to cell junctions such as desmosomes . Keratin forms intermediate filament bundles which are tough and strong

Keratin cycfoplasmic intermediate filaments binds with plasma membrane of cell cell junctions and cell substrate junctions

Other proteins such as actin and alpha tubulin beta tubulin are cytosketal protein which participates in internal and external cell movements but keratin is not involved