TABLE 1.

CHX blocks destabilization of coreceptor RNAs in signaled DP thymocytes but does not interfere with TCR-CD2 signal transduction^a

DP thymocyte stimulant	Relative content of:
	CD4 RNA		CD8α RNA		CD5 RNA
	No CHX	CHX	No CHX	CHX	No CHX	CHX
Medium	1.0	1.0	1.0	1.0	1.0	1.0
X(TCR + CD2)	0.2	0.8	0.2	0.9	4.0	6.1

^aDP thymocytes were stimulated for 7 h with either medium or immobilized anti-TCR and anti-CD2 MAbs [X(TCR + CD2)] in the presence or absence of CHX (10 μg/ml) and then analyzed by Northern blot hybridization with the indicated RNA probes. Samples were quantitated by densitometry, using the amount of β-actin RNA present in each sample as a loading control. The contents of RNAs encoding CD4, CD8α, and CD5 in TCR- and CD2-stimulated DP thymocytes were expressed relative to that of unstimulated DP thymocytes, which was set at 1.0 for each sample.