PDBsum entry 2vrd

Nuclear protein

PDB id: 2vrd

Contents

Protein chain

61 a.a. *

Metals

_ZN

* Residue conservation analysis

PDB id:

2vrd

Name:

Nuclear protein

Title:

The structure of the zinc finger from the human spliceosomal protein u1c

Structure:

U1 small nuclear ribonucleoprotein c. Chain: a. Fragment: zinc finger domain, residues 1-61. Synonym: u1 snrnp protein c, u1c protein, u1-c. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Expressed in: escherichia coli. Expression_system_taxid: 562.

NMR struc:

47 models

Authors:

Y.Muto,D.Pomeranz-Krummel,C.Oubridge,H.Hernandez,C.Robinson, D.Neuhaus,K.Nagai

Key ref:

Y.Muto et al. (2004). The structure and biochemical properties of the human spliceosomal protein U1C. J Mol Biol, 341, 185-198. PubMed id: 15312772 DOI: 10.1016/j.jmb.2004.04.078

Date:

31-Mar-08 Release date: 08-Apr-08

Supersedes:

1uw2

Protein chain

P09234  (RU1C_HUMAN) -  U1 small nuclear ribonucleoprotein C from Homo sapiens

Seq: 159 a.a.

Struc: 61 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1016/j.jmb.2004.04.078

J Mol Biol 341:185-198 (2004)

PubMed id: 15312772

The structure and biochemical properties of the human spliceosomal protein U1C.

Y.Muto, D.Pomeranz Krummel, C.Oubridge, H.Hernandez, C.V.Robinson, D.Neuhaus, K.Nagai.

ABSTRACT

The spliceosomal U1C protein is critical to the initiation and regulation of precursor messenger RNA (pre-mRNA) splicing, as part of the U1 small nuclear ribonucleoprotein particle (snRNP). We have produced full-length and 61 residue constructs of human U1C in soluble form in Escherichia coli. Atomic absorption spectroscopy and mass spectrometry show that both constructs contain one Zn atom and are monomeric. Gelmobility-shift assays showed that one molecule of recombinant U1C, either full-length or 61 residue construct, can be incorporated into the U1 snRNP core domain in the presence of U1 70k. This result is in perfect agreement with the previous experiment with U1C isolated from the HeLa U1 snRNP showing that the recombinant U1C is functionally active. We have determined the solution structure of the N-terminal 61 residue construct of U1C by NMR. A Cys(2)His(2)-type zinc finger, distinct from the TFIIIA-type, is extended at its C terminus by two additional helices. The two Zn-coordinating histidine residues are separated by a five residue loop. The conserved basic residues in the first two helices and the intervening loop may be involved in RNA binding. The opposite beta-sheet face with two surface-exposed Tyr residues may be involved in protein contacts. Both the full-length and 61 residue constructs of human U1C fail to bind RNA containing the 5' splice site sequence, in contrast to what has been reported for the Saccharomyces cerevisiae orthologue.

Selected figure(s)

Figure 5.
Figure 5. Solution structure of human U1C. A, Stereo ribbon representation of the lowest-energy structure. A blue arrow indicates the b-strands and a red coil indicates the helical region. Some aromatic residues including the two tyrosine residues (Y5 and Y12) on the b-strands as well as the Zn-coordinating residues (Cys6, Cys9, His24 and His30) are indicated. B, The surface representation of U1C with surface electrostatic potential. The surface formed by the three a-helices displays many positively charged amino acid residues. Blue, positively charged; red, negatively charged. C, The b-strand surface rich in aromatic and negatively charged amino acid residues. Figures were drawn using MOLSCRIPT[53.] and GRASP. [54.]

Figure 6.
Figure 6. Filter-binding assay of the 5' splice site binding to U1 snRNP and U1C protein. ( o ) The reconstituted U1 snRNP; (sB) full-length U1C. The experiments were done in triplicate and error bars are shown for U1 snRNP only for clarity.

The above figures are reprinted by permission from Elsevier: J Mol Biol (2004, 341, 185-198) copyright 2004.

Figures were selected by an automated process.