Nonsense-mediated mRNA decay (NMD) represents a surveillance mechanism that recognizes and degrades mRNAs with stop codons in unfavorable environment for efficient translation termination, e.g. due to long 3’UTRs [1].
The group of Prof. Oliver Mühlemann used microarrays to identify genome-wide NMD substrates and discovered that almost all mRNAs encoding NMD factors harbor long 3’UTRs and are under feedback control by NMD [2]. Such autoregulation ensures the stability of NMD process that translates to a stability of the large repertoire of NMD substrates, thus maintaining the balance of a variety of cellular processes.

References:

1. L. Stalder, O. Mühlemann;
   "The meaning of nonsense"
   Trends in Cell Biol., 18, 315-321, (2008); doi:10.1016/j.tcb.2008.04.005.
2. H. Yepiskoposyan, F. Aeschimann, D. Nilsson, M. Okoniewski, O. Mühlemann;
   "Autoregulation of the nonsense-mediated mRNA decay pathway in human cells"
   RNA, 17, 2108-2118, (2011); doi:10.1261/rna.030247.111.