Question

Signaling through the pre-TCR results in:

A. maturation to the DN4 stage.
B. suppression of TCR β-chain rearrangement.
C. cessation of proliferation.
D. TCR α-chain rearrangement.
E. All of the above

Answer 1

The pre-TCR signaling in T cell development leads to maturation to the DN4 stage, suppression of TCR β-chain rearrangement, cessation of proliferation, and TCR α-chain rearrangement.

Step-by-step explanation:

The pre-TCR (pre-T cell receptor) is a receptor that plays a crucial role in the development of T cells. Signaling through the pre-TCR has several effects on T cell maturation:

1. Maturation to the DN4 stage: This is a specific stage of T cell development where T cells undergo further differentiation and maturation.
2. Suppression of TCR β-chain rearrangement: The pre-TCR signaling prevents further rearrangement of the TCR β-chain genes, allowing the T cell to proceed with maturation.
3. Cessation of proliferation: The pre-TCR signaling halts the proliferation of T cells, preventing excessive cell division.
4. TCR α-chain rearrangement: After signaling through the pre-TCR, T cells undergo rearrangement of the TCR α-chain genes to complete their development.

Therefore, the correct answer is E. All of the above.