3 other than that the subunits of the turc and arp

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Unformatted text preview: Mad2 checkpoint protein becomes activated at the unattached kinetochore. Activated Mad2 binds to and inhibits APC/C. Thus, APC/C cannot poly ­ubiquitinate securin to cause its degradation. Since securin is not degraded, it stays bound to the protease separase, preventing separase from cleaving cohesin. 2. The Examinin receptor tyrosine kinase (RTK), like many other RTKs, is endocytosed only after ligand binding. A mutant Examinin that is not active as a kinase is not endocytosed even after ligand binding. Based on what you know about these other RTKs, what is the molecular mechanism that accounts for the endocytosis of Examinin only after ligand binding. (4 points) Ligand binding leads to activation and phosphorylation of Examinin. An E3 (with SH2 domain) binds (tyrosine) phosphorylated Examinin. E3 ubiquitinates Examinin, leading to its recruitment into endocytic...
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