Question
These molecules bind to the V-beta chain of T-cell receptors, giving them a greater number of potential targets than those restricted to unique alpha and beta receptor clonotypes. For 10 points each:
[10h] Name these molecules that bind class II MHCs and T-cell receptors outside of the normal peptide-binding groove, resulting in T-cell overactivation. These molecules act as potent exotoxins in scarlet fever.
ANSWER: superantigens [accept SAgs; prompt on antigens]
[10e] Superantigen engagement causes T-cells to activate signaling through the Src (“sark”) family of kinases, which are enzymes that transfer these groups from donors like ATP to their substrates.
ANSWER: phosphates
[10m] In the absence of a Src kinase, SAgs activate T-cells through the activation of phospholipase C by the alpha-11 subunit of these proteins. These proteins couple with receptors that cross the cell membrane seven times.
ANSWER: G proteins [or guanine-nucleotide-binding proteins; accept heterotrimeric G proteins]
<AY, Biology>
Summary
| 2023 ARCADIA at UC Berkeley | Premiere | Y | 2 | 20.00 | 100% | 100% | 0% |
| 2023 ARCADIA at Carleton University | Premiere | Y | 3 | 10.00 | 67% | 33% | 0% |
| 2023 ARCADIA at Claremont Colleges | Premiere | Y | 1 | 20.00 | 100% | 100% | 0% |
| 2023 ARCADIA at Indiana | Premiere | Y | 5 | 16.00 | 80% | 60% | 20% |
| 2023 ARCADIA at RIT | Premiere | Y | 2 | 10.00 | 50% | 50% | 0% |
| 2023 ARCADIA at WUSTL | Premiere | Y | 3 | 20.00 | 100% | 67% | 33% |
Data
| McDouble West-Carleton | Waterloo | 0 | 10 | 0 | 10 |
| Ottawa C | Ottawa A | 0 | 0 | 0 | 0 |
| Toronto Ray of Sun in the Sky | Ottawa B | 0 | 10 | 10 | 20 |