Lead influences translational or posttranslational regulation of ia expression and increases invariant chain expression in mouse B cells

✍ Scribed by McCabe, Michael J. ;Dias, James A. ;Lawrence, David A.

• Book ID: 102875633
• Publisher: John Wiley and Sons
• Year: 1991
• Tongue: English
• Weight: 820 KB
• Volume: 6
• Category: Article
• ISSN: 0887-2082
• DOI: 10.1002/jbt.2570060406

✦ Synopsis

The molecular mechanisms governing the increased cell surface expression of major histocompatibility complex (MHC) class I1 molecules (Ia) on lead-treated mouse B cells was investigated. Lead has been shown to directly cause a selective, two-fold increase in the B cell's surface density of both products of the I region of the mouse MHC, I-A and I-E. In the present study, Western blot analysis showed that Pb increases the total cellular pool of I-A P-chain by twofold. The increase in cellular I-A was not found to be due to increased messenger RNA (mRNA) for either the a-or the P-chain of I-A. Biosynthetic labeling studies showed that Pb increases the translation or the stability of the Ia-associated invariant chain (Ii or y ) and possibly the P-chain of Ia. Collectively these results suggest that Pb increases the B cell's surface Ia by influencing translational or posttranslational regulation of Ia and/or Ia-associated chains.