Question

These proteins are found in the budding yeast Saccharomyces cerevisiae; they form "neck filaments" between a mother cell and its growing bud, and help polarize protein distribution between the two. These proteins ...

A. can polymerize to form filaments and sheets.
B. bind GTP.
C. are also involved in contractile ring formation during cytokinesis in animal cells.
D. form filaments that are thought to be nonpolar.
E. All of the above.

Answer 1

Cytoskeletal proteins in Saccharomyces cerevisiae can polymerize, bind GTP, assist with contractile ring formation during cytokinesis, and form polar filaments.

Step-by-step explanation:

The proteins referred to in the question that are found in the budding yeast Saccharomyces cerevisiae, form 'neck filaments' between a mother cell and its bud, and help polarize protein distribution are namely cytoskeletal elements, which could be either microfilaments or microtubules based on the description provided. These proteins have several key features:

• They can polymerize to form structures such as filaments and sheets.
• Some of these proteins bind GTP, which is an energy source for tubulin in microtubules, similar to the action of ATP for actin in microfilaments.
• They are involved in contractile ring formation during cytokinesis, which is a process seen in both yeasts and animal cells.
• Actin filaments are polar, meaning they have distinct ends with different polymerization rates at each end.