Correct option is B
The incorrect statement is (b). In fact, actin specifically binds ATP, while tubulin binds GTP. Both actin and tubulin are essential cytoskeletal proteins, but their nucleotide binding preferences are opposite to the statement in (b).
Actin uses ATP to polymerize and form filaments, whereas tubulin uses GTP in a similar process to form microtubules.
The other statements about actin and tubulin are accurate. Both actin and tubulin are thought to have evolved from a common ancestor, and proteins like FtsZ (a tubulin relative) and MreB (an actin relative) play crucial roles in prokaryotic cell division and shape maintenance.
Information Booster:
Actin binds ATP and is a key component of the cytoskeleton, involved in processes like cell shape maintenance, motility, and division.
Tubulin binds GTP and forms microtubules, which are critical for processes such as mitosis, intracellular transport, and maintaining cell structure.
FtsZ is a tubulin-related protein found in prokaryotes, forming a contractile ring during cell division, similar to the role of tubulin in eukaryotic cells.
MreB is an actin-related protein that forms filaments responsible for maintaining the cell shape in prokaryotes, analogous to actin filaments in eukaryotic cells.
Additional Information:
(a) Actin and tubulin proteins appear to have arisen from single-copy genes, present before multicellular eukaryotes diverged: This statement is correct. Both actin and tubulin proteins are considered to have evolved early in eukaryotic evolution and are present in most eukaryotic and some prokaryotic cells.
(c) FtsZ, a tubulin relative, forms a filamentous ring needed to affect cell division in certain prokaryotic species: This is correct. FtsZ is responsible for forming a Z-ring in prokaryotic cells, a key structure in cell division, similar to the role of tubulin in eukaryotic cells.
(d) MreB, an actin relative, forms filaments required for the cell shape in certain prokaryotic species: This is correct. MreB is an actin-related protein in prokaryotes, playing a vital role in maintaining cell shape, similar to the function of actin in eukaryotic cells.
