LEC: A multipurpose tool

The transcription process converts information encoded in DNA into various forms of RNA, including messenger RNA, which carries protein-making instructions, and snRNAs, which partner with proteins to form small nuclear ribonucleoproteins (snRNPs). In recent years, Investigator Ali Shilatifard, PhD, and his team have focused their work on a family of factors called ELL (Eleven-nineteen lysine-rich leukemia gene), which speed up the rate at which genes are expressed to help the transcription process along.

In their latest investigation, the Shilatifard Lab discovered that a rarely studied factor known as the Little Elongation Complex (LEC) plays a critical and previously unknown role in the transcription of small nuclear RNAs (snRNA). “We have found that LEC not only has a role in this process—it is like the ‘Swiss Army knife’ of snRNA transcription,” says Shilatifard. “LEC does it all.” The findings shed new light on the mystery of snRNA transcription, which is vitally important to gene expression and regulation, but has been poorly understood until now.

“As biologists we are very interested in defining the molecular machineries involved in life, and snRNA are very important in life,” Shilatifard says. “The nucleus is a suitcase with all of the DNA information packaged in it. You need specific machinery to identify the right information to unpack to perform the exact process that’s needed. Now we understand another piece of that machinery.”

Understanding LEC and the machinery of snRNA transcription may also have implications for the treatment of disease. It could, for example, open the door to novel approaches for treating diseases that are associated with defective snRNA function and splicing, such as spinal muscular atrophy and Prader-Willi syndrome, or for attacking cancer cells, whose proteins may also undergo splicing.

The study was published in the August 22, 2013, issue of the journal Molecular Cell.