Welcome! Click here to login or here to register.
Catalytic RNA molecules
Enzymatic complexes
Draw a picture

Bujnicki Lab Homepage

"A doughnut-shaped heteromer of human Sm-like proteins binds to the 3'-end of U6 snRNA, thereby facilitating U4/U6 duplex formation in vitro."

Achsel T, Brahms H, Kastner B, Bachi A, Wilm M, Luhrmann R

Published 1999-10-15 in EMBO J volume 18 .

Pubmed ID: 10523320

We describe the isolation and molecular characterization of seven distinct proteins present in human [U4/U6.U5] tri-snRNPs. These proteins exhibit clear homology to the Sm proteins and are thus denoted LSm (like Sm) proteins. Purified LSm proteins form a heteromer that is stable even in the absence of RNA and exhibits a doughnut shape under the electron microscope, with striking similarity to the Sm core RNP structure. The purified LSm heteromer binds specifically to U6 snRNA, requiring the 3'-terminal U-tract for complex formation. The 3'-end of U6 snRNA was also co-precipitated with LSm proteins after digestion of isolated tri-snRNPs with RNaseT(1). Importantly, the LSm proteins did not bind to the U-rich Sm sites of intact U1, U2, U4 or U5 snRNAs, indicating that they can only interact with a 3'-terminal U-tract. Finally, we show that the LSm proteins facilitate the formation of U4/U6 RNA duplices in vitro, suggesting that the LSm proteins may play a role in U4/U6 snRNP formation.

This publication refers to the following RNApathwaysDB entries:


Add your own comment!

There are no comments yet.
Welcome stranger! Click here to login or here to register.