Reviewed, UniProtKB/Swiss-Prot P50539 (MXI1_HUMAN)

Names and origin

Protein names

Recommended name:
    MAX-interacting protein 1
      Short name=Protein MXI1

Gene names

Name:

MXI1

Organism

Homo sapiens (Human)

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo

Protein attributes

Sequence length	228 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Transcriptional repressor. MXI1 binds with MAX to form a sequence-specific DNA-binding protein complex which recognizes the core sequence 5'-CAC[GA]TG-3'. MXI1 thus antagonizes MYC transcriptional activity by competing for MAX.
Subunit structure	Interacts with SMC3 By similarity. Efficient DNA binding requires dimerization with another bHLH protein. Binds DNA as a heterodimer with MAX. Interacts with RNF17 By similarity.
Subcellular location	Nucleus.
Tissue specificity	High levels found in the brain, heart and lung while lower levels are seen in the liver, kidney and skeletal muscle.
Involvement in disease	Defects in MXI1 are found in some patients with prostate cancer (CaP) [MIM:176807].
Sequence similarities	Contains 1 basic helix-loop-helix (bHLH) domain.

Ontologies

Keywords
Biological process	Transcription Transcription regulation
Cellular component	Nucleus
Coding sequence diversity	Alternative splicing
Disease	Disease mutation Proto-oncogene
Ligand	DNA-binding
Molecular function	Repressor
Gene Ontology (GO)
Biological process	cytoplasmic sequestering of transcription factor Ref.1 Traceable author statement. Source: ProtInc negative regulation of cell proliferation Traceable author statement. Source: ProtInc regulation of transcription, DNA-dependent Inferred from electronic annotation. Source: UniProtKB-KW transcription Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	nucleus Ref.1 Traceable author statement. Source: ProtInc
Molecular function	DNA binding Ref.1 Traceable author statement. Source: ProtInc transcription corepressor activity Ref.1 Traceable author statement. Source: ProtInc
Complete GO annotation...

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: P50539-1)

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

Isoform 2 (identifier: P50539-2)

The sequence of this isoform differs from the canonical sequence as follows:
     1-36: Missing.

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 228	228	MAX-interacting protein 1		PRO_0000127285
Regions
	Domain	81 – 120	40	Helix-loop-helix motif
	DNA binding	69 – 80	12	Basic motif
Natural variations
	Alternative sequence	1 – 36	36	Missing in isoform 2.		VSP_012825
	Natural variant	152	1	E → A in prostate cancer. Ref.8		VAR_004499
Experimental info
	Sequence conflict	61	1	S → T in AAA75508. Ref.1

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 [UniParc]. Last modified October 17, 2006. Version 2. Checksum: 82F83F499B907DD3	FASTA	228	26,062
	10 20 30 40 50 60 MERVKMINVQ RLLEAAEFLE RRERECEHGY ASSFPSMPSP RLQHSKPPRR LSRAQKHSSG 70 80 90 100 110 120 SSNTSTANRS THNELEKNRR AHLRLCLERL KVLIPLGPDC TRHTTLGLLN KAKAHIKKLE 130 140 150 160 170 180 EAERKSQHQL ENLEREQRFL KWRLEQLQGP QEMERIRMDS IGSTISSDRS DSEREEIEVD 190 200 210 220 VESTEFSHGE VDNISTTSIS DIDDHSSLPS IGSDEGYSSA SVKLSFTS
	Isoform 2. Checksum: 3D8B586EEA033591	FASTA	192	21,767
	10 20 30 40 50 60 MPSPRLQHSK PPRRLSRAQK HSSGSSNTST ANRSTHNELE KNRRAHLRLC LERLKVLIPL 70 80 90 100 110 120 GPDCTRHTTL GLLNKAKAHI KKLEEAERKS QHQLENLERE QRFLKWRLEQ LQGPQEMERI 130 140 150 160 170 180 RMDSIGSTIS SDRSDSEREE IEVDVESTEF SHGEVDNIST TSISDIDDHS SLPSIGSDEG 190 YSSASVKLSF TS

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Mxi1, a protein that specifically interacts with Max to bind Myc-Max recognition sites." Zervos A.S., Gyuris J., Brent R. Cell 72:223-232(1993) [PubMed: 8425219] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[2]	Erratum Zervos A.S., Gyuris J., Brent R. Cell 79:388-388(1994)
[3]	"Genomic organization of human MXI1, a putative tumor suppressor gene." Wechsler D.S., Shelly C.A., Dang C.V. Genomics 32:466-470(1996) [PubMed: 8838813] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[4]	"Expression, regulation and polymorphism of the mxi1 genes." Shimizu E., Shirasawa H., Kodama K., Sato T., Shimizu B. Gene 176:45-48(1996) [PubMed: 8918230] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2).
[5]	"Cloning of human full open reading frames in Gateway(TM) system entry vector (pDONR201)." Halleck A., Ebert L., Mkoundinya M., Schick M., Eisenstein S., Neubert P., Kstrang K., Schatten R., Shen B., Henze S., Mar W., Korn B., Zuo D., Hu Y., LaBaer J. Submitted (JUN-2004) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
[6]	"The DNA sequence and comparative analysis of human chromosome 10." Deloukas P., Earthrowl M.E., Grafham D.V., Rubenfield M., French L., Steward C.A., Sims S.K., Jones M.C., Searle S., Scott C., Howe K., Hunt S.E., Andrews T.D., Gilbert J.G.R., Swarbreck D., Ashurst J.L., Taylor A., Battles J. , Bird C.P., Ainscough R., Almeida J.P., Ashwell R.I.S., Ambrose K.D., Babbage A.K., Bagguley C.L., Bailey J., Banerjee R., Bates K., Beasley H., Bray-Allen S., Brown A.J., Brown J.Y., Burford D.C., Burrill W., Burton J., Cahill P., Camire D., Carter N.P., Chapman J.C., Clark S.Y., Clarke G., Clee C.M., Clegg S., Corby N., Coulson A., Dhami P., Dutta I., Dunn M., Faulkner L., Frankish A., Frankland J.A., Garner P., Garnett J., Gribble S., Griffiths C., Grocock R., Gustafson E., Hammond S., Harley J.L., Hart E., Heath P.D., Ho T.P., Hopkins B., Horne J., Howden P.J., Huckle E., Hynds C., Johnson C., Johnson D., Kana A., Kay M., Kimberley A.M., Kershaw J.K., Kokkinaki M., Laird G.K., Lawlor S., Lee H.M., Leongamornlert D.A., Laird G., Lloyd C., Lloyd D.M., Loveland J., Lovell J., McLaren S., McLay K.E., McMurray A., Mashreghi-Mohammadi M., Matthews L., Milne S., Nickerson T., Nguyen M., Overton-Larty E., Palmer S.A., Pearce A.V., Peck A.I., Pelan S., Phillimore B., Porter K., Rice C.M., Rogosin A., Ross M.T., Sarafidou T., Sehra H.K., Shownkeen R., Skuce C.D., Smith M., Standring L., Sycamore N., Tester J., Thorpe A., Torcasso W., Tracey A., Tromans A., Tsolas J., Wall M., Walsh J., Wang H., Weinstock K., West A.P., Willey D.L., Whitehead S.L., Wilming L., Wray P.W., Young L., Chen Y., Lovering R.C., Moschonas N.K., Siebert R., Fechtel K., Bentley D., Durbin R.M., Hubbard T., Doucette-Stamm L., Beck S., Smith D.R., Rogers J. Nature 429:375-381(2004) [PubMed: 15164054] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[7]	"Redefinition of the coding sequence of the MXI1 gene and identification of a polymorphic repeat in the 3' non-coding region that allows the detection of loss of heterozygosity of chromosome 10q25 in glioblastomas." Albarosa R., Didonato S., Finocchiaro G. Hum. Genet. 95:709-711(1995) [PubMed: 7789959] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 216-228.
[8]	"Mutation of the MXI1 gene in prostate cancer." Eagle L.R., Yin X., Brothman A.R., Williams B.J., Atkin N.B., Prochownik E.V. Nat. Genet. 9:249-255(1995) [PubMed: 7773287] [Abstract] Cited for: VARIANT PROSTATE CANCER ALA-152.
+	Additional computationally mapped references.

Web resources

Atlas of Genetics and Cytogenetics in Oncology and Haematology

Cross-references

Sequence databases
EMBLGenBankDDBJ	L07648 mRNA. Translation: AAA75508.1. U32515 , U32512, U32513, U32514 Genomic DNA. Translation: AAC50446.1. D63940 mRNA. Translation: BAA09972.1. CR536576 mRNA. Translation: CAG38813.1. AL360182 Genomic DNA. Translation: CAI15476.1. AL360182 Genomic DNA. Translation: CAI15479.1. S78470 Genomic DNA. Translation: AAD14282.1.
IPI	IPI00301031. IPI00552166.
PIR	A45182.
RefSeq	NP_005953.4.
UniGene	Hs.501023 Hs.602078
3D structure databases
HSSP	HSSP built from PDB template 1NLW based on UniProtKB Q05195.
SMR	P50539. Positions 68-146.
ModBase	Search...
Protein-protein interaction databases
DIP	DIP:205N.
Genome annotation databases
Ensembl	ENSG00000119950. Homo sapiens. [Contig view]
GeneID	4601.
NMPDR	fig|9606.3.peg.4635.
Organism-specific databases
GeneCards	GC10P111957.
HGNC	HGNC:7534. MXI1.
MIM	176807. phenotype. 600020. gene.
Orphanet	1331. Prostate cancer, familial.
PharmGKB	PA31335.
GenAtlas	Search...
Phylogenomic databases
HOVERGEN	P50539.
OMA	P50539. MERVRMI.
Gene expression databases
ArrayExpress	P50539.
Bgee	P50539.
CleanEx	HS_MXI1.
GermOnline	ENSG00000119950. Homo sapiens.
Family and domain databases
InterPro	IPR001092. HLH_basic. IPR011598. HLH_DNA_bd. [Graphical view]
Gene3D	G3DSA:4.10.280.10. HLH_DNA_bd. 1 hit.
Pfam	PF00010. HLH. 1 hit. [Graphical view]
SMART	SM00353. HLH. 1 hit. [Graphical view]
PROSITE	PS50888. HLH. 1 hit. [Graphical view]
ProtoNet	Search...
Other Resources
NextBio	17692.
SOURCE	Search...

Entry information

Entry name

MXI1_HUMAN

Accession

Primary (citable) accession number: P50539
Secondary accession number(s): Q15887, Q6FHW2

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1996
Last sequence update:	October 17, 2006
Last modified:	June 16, 2009
This is version 80 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)