Question

True or False

26._____ Unlike cadherins, selectins do not require Ca²⁺for their function.

27._____ Cofilin binds ADP-actin filaments to accelerate assembly.

28._____ All members of the cadherin superfamily have identical protein structures.

29._____ Nonsense or truncating mutations are more frequently observed in tumor suppressor genes than they are observed in oncogenes.

30._____ Adherens junctions are anchorage sites for actin filaments.

Answer 1

26. FALSE, Selectins are adhesion molecules and have calcium ions intereaction, so this statement is not correct.

27.FALSE. Its a binding factor and necessary for the re arrangement of filament (actin) and responsible for dis-assembly, so this statement is not true

28. FALSE. This superfamily of protein is diverse (different) on the basis of their structure like adhesin and GPCR; so provided statement is not relevant.

29. TRUE. Alteration in the DNA sequence causes non-sense (change in single base pair) or truncated mutation (to create short sequence) and its impact is more frequent in tumor suppressor genes like p53 as compared to the oncogene, so this is a correct statement

30. TRUE, Adherence junction binds with the actin filament through two abundant matrix proteins, 1 integrin, 2. Cadherin, therefore this statement is correctly written.