Mitotic cyclin levels are regulated in cycling embryonic cells of Xenopus. In la
ID: 74830 • Letter: M
Question
Mitotic cyclin levels are regulated in cycling embryonic cells of Xenopus. In late anaphase, the anaphase promoting complex (APC) [____] mitotic cyclins. As the cyclins are degraded by proteasomes, [____] activity declines precipitously, triggering the onset of [____]. APC activity is directed toward mitotic cyclins, and once the APC activity is inhibited in [____], the concentration of mitotic cyclin increases, eventually reaching a high enough level to stimulate entry into the subsequent [____].
Please pick one.
(1) polyubiquitinylates; APC; anaphase; G2; telophase
(2) phosphorylates; MPF; mitotic prophase; telophase; prophase
(3) removes; G1 cyclin-CDK; metaphase; telophase; G0
(4) polyubiquitinylates; MPF kinase; telophase; G1; mitotic prophase
(5) degrades; G2 cyclin-CDK; anaphase; G1; telophase
Explanation / Answer
Answer is (5)