Author Archives: Kristina Krumpos

Karyopherin Alpha

PDB ID:   1EE5

Number of Polypeptide Chains in the Protein:   2

Chain Designation:  

Chain 1: A; Chain 2: B

Gene Names:  

SRP1, KAP60, YNL189W, N1606

PDB Deposition Title:  

YEAST KARYOPHERIN (IMPORTIN) ALPHA IN A COMPLEX WITH A NUCLEOPLASMIN NLS PEPTIDE

Primary Citation Title:  

Crystallographic analysis of the specific yet versatile recognition of distinct nuclear localization signals by karyopherin alpha.

Citation Authors:  

Conti, E., Kuriyan, J.

Citation Journal:  

(2000) Structure Fold.Des. 8: 329-338

Related PDB Entries:  

1BK5, 1BK6, 1UN0, 1EE4, 1WA5

 


Information for Chain A;  UniprotKB Accession Number:  Q02821

Primary Structure

Length of the Chain (from Uniprot Q02821):  542

FASTA Sequence for the chain (from Uniprot Q02821):

>sp|Q02821|IMA1_YEAST Importin subunit alpha OS=Saccharomyces cerevisiae (strain ATCC 204508 / S288c) GN=SRP1 PE=1 SV=1
MDNGTDSSTSKFVPEYRRTNFKNKGRFSADELRRRRDTQQVELRKAKRDEALAKRRNFIP
PTDGADSDEEDESSVSADQQFYSQLQQELPQMTQQLNSDDMQEQLSATVKFRQILSREHR
PPIDVVIQAGVVPRLVEFMRENQPEMLQLEAAWALTNIASGTSAQTKVVVDADAVPLFIQ
LLYTGSVEVKEQAIWALGNVAGDSTDYRDYVLQCNAMEPILGLFNSNKPSLIRTATWTLS
NLCRGKKPQPDWSVVSQALPTLAKLIYSMDTETLVDACWAISYLSDGPQEAIQAVIDVRI
PKRLVELLSHESTLVQTPALRAVGNIVTGNDLQTQVVINAGVLPALRLLLSSPKENIKKE
ACWTISNITAGNTEQIQAVIDANLIPPLVKLLEVAEYKTKKEACWAISNASSGGLQRPDI
IRYLVSQGCIKPLCDLLEIADNRIIEVTLDALENILKMGEADKEARGLNINENADFIEKA
GGMEKIFNCQQNENDKIYEKAYKIIETYFGEEEDAVDETMAPQNAGNTFGFGSNVNQQFN
FN

Secondary Structures (DSSP defined; from RCSB PDB)

Helical Structures:  Number of Helices:  35;  Percentage of Residues:  73

Beta Strands:  Number of Strands:  0;  Percentage of Residues:  0

Secondary Structure Map:

 

Tertiary Structure

Number of Domains Along Chain A:  1

CATH Domain IDs:  1ee5A00

CATH Classes:  A00: Mainly Alpha

CATH Architectures:  A00: Alpha Horseshoe

CATH Topologies:  A00: Leucine-rich Repeat Variant

Topological Diagrams:

 

 

Function and Ligand Binding Site

Excerpt from Abstract:

Karyopherin alpha (importin alpha) is an adaptor molecule that recognizes proteins containing nuclear localization signals (NLSs). The prototypical NLS that is able to bind to karyopherin alpha is that of the SV40 T antigen, and consists of a short positively charged sequence motif. Distinct classes of NLSs (monopartite and bipartite) have been identified that are only partly conserved with respect to one another but are nevertheless recognized by the same receptor.

Description of Function from Uniprot:

Binds specifically and directly to substrates containing either a simple or bipartite NLS motif. Promotes docking of import substrates to the nuclear envelope. Seems to act as a cytosolic receptor for both simple and bipartite NLS motifs (By similarity).

Selected Molecular Function GO Terms:

GO ID: 0006606, Name: Protein import into nucleus, Definition: The directed movement of a protein from the cytoplasm to the nucleus.

  ||  

GO ID: 0008565, Name: Protein transporter activity, Definition: Enables the directed movement of proteins into, out of or within a cell, or between cells.

  ||  

GO ID: 0005515, Name: Protein binding, Definition: Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).

EC Number:   N/A

EC Description:   

N/A

Major Organic Ligand:   CITRATE ANION

Ligand Binding Residues:

His 261, Asn 263, Gln 297, Lys 300

Ligand Binding Site: