Reviewed, UniProtKB/Swiss-Prot Q9GZQ8 (MLP3B_HUMAN)

Names and origin

Protein names

Recommended name:
    Microtubule-associated proteins 1A/1B light chain 3B
Alternative name(s):
    Microtubule-associated protein 1 light chain 3 beta
    MAP1A/1B light chain 3 B
    MAP1A/MAP1B LC3 B
    MAP1 light chain 3-like protein 2
    Autophagy-related protein LC3 B
    Autophagy-related ubiquitin-like modifier LC3 B

Gene names

Name:	MAP1LC3B
Synonyms:	MAP1ALC3

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	125 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Probably involved in formation of autophagosomal vacuoles (autophagosomes).
Subunit structure	3 different light chains, LC1, LC2 and LC3, can associate with MAP1A and MAP1B proteins By similarity.
Subcellular location	Cytoplasm. Endomembrane system; Lipid-anchor. Cytoplasmic vesicle › autophagosome membrane; Lipid-anchor. Note: LC3-II binds to the autophagic membranes.
Tissue specificity	Most abundant in heart, brain, skeletal muscle and testis. Little expression observed in liver. Ref.3
Post-translational modification	The precursor molecule is cleaved by APG4B/ATG4B to form LC3-I. This is activated by APG7L/ATG7, transferred to ATG3 and conjugated to phospholipid to form LC3-II. Ref.6 Ref.7
Sequence similarities	Belongs to the MAP1 LC3 family.
Caution	Ref.3 has shown that the protein is cleaved at Lys-122 but Ref.7 has shown that the cleavage site is at Gly-120 as in other mammalian orthologs.

Ontologies

Keywords
Biological process	Autophagy Ubl conjugation pathway
Cellular component	Cytoplasm Cytoplasmic vesicle Membrane Microtubule
PTM	Lipoprotein
Technical term	3D-structure
Gene Ontology (GO)
Biological process	autophagy Inferred from electronic annotation. Source: UniProtKB-KW modification-dependent protein catabolic process Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	autophagic vacuole membrane Inferred from electronic annotation. Source: UniProtKB-SubCell cytoplasmic vesicle Inferred from electronic annotation. Source: UniProtKB-SubCell endomembrane system Inferred from electronic annotation. Source: UniProtKB-SubCell microtubule Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	protein binding Ref.6 Ref.7 Inferred from physical interaction. Source: UniProtKB
Complete GO annotation...

Binary interactions

With	Entry	#Exp.	IntAct	Notes
SQSTM1	Q13501	1	EBI-373144,EBI-307104
Sqstm1	Q64337	2	EBI-373144,EBI-645025	From a different organism.
UPF2	Q9HAU5	1	EBI-373144,EBI-372073

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Initiator methionine

1

1

Removed By similarity

Chain

2 – 120

119

Microtubule-associated proteins 1A/1B light chain 3B

PRO_0000017198

Propeptide

121 – 125

5

Removed in mature form

PRO_0000017199

Amino acid modifications

Lipidation

120

1

Phosphatidylethanolamine amidated glycine Probable

Experimental info

Mutagenesis

120

1

G → A: No processing of precursor. Ref.7

Mutagenesis

122

1

K → A: No effect on processing of precursor. Ref.7

Sequence conflict

61

1

S → G in AAH67797. Ref.5

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

125

Helix Strand Turn

Details...

Helix

7 – 10

4

Helix

13 – 26

14

Beta strand

30 – 37

8

Beta strand

51 – 55

5

Helix

60 – 71

12

Beta strand

79 – 83

5

Turn

84 – 86

3

Helix

95 – 102

8

Beta strand

109 – 115

7

Helix

116 – 121

6

Sequences

	Sequence		Length	Mass (Da)
	Q9GZQ8-1 [UniParc]. Last modified January 23, 2007. Version 3. Checksum: BB141DEC7653E83F	FASTA	125	14,688
	10 20 30 40 50 60 MPSEKTFKQR RTFEQRVEDV RLIREQHPTK IPVIIERYKG EKQLPVLDKT KFLVPDHVNM 70 80 90 100 110 120 SELIKIIRRR LQLNANQAFF LLVNGHSMVS VSTPISEVYE SEKDEDGFLY MVYASQETFG MKLSV

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Gene expression profiles in human non-small and small-cell lung cancers." Difilippantonio S., Chen Y., Pietas A., Schluens K., Pacyna-Gengelbach M., Deutschmann N., Padilla-Nash H.M., Ried T., Petersen I. Eur. J. Cancer 39:1936-1947(2003) [PubMed: 12932674] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Lung carcinoma.
[2]	"The gene expression profiling of sporadic pheochromocytoma and novel full-length cDNAs cloning." Yang Y.-S., Song H.-D., Peng Y.-D., Huang Q.-H., Li R.-Y., Zhu Z.-D., Hu R.-M., Han Z.-G., Chen J.-L. Endocr. Relat. Cancer 10:621-627(2003) [PubMed: 14713272] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Pheochromocytoma.
[3]	"Post-translational modifications of three members of the human MAP1LC3 family and detection of a novel type of modification for MAP1LC3B." He H., Dang Y., Dai F., Guo Z., Wu J., She X., Pei Y., Chen Y., Ling W., Wu C., Zhao S., Liu J.O., Yu L. J. Biol. Chem. 278:29278-29287(2003) [PubMed: 12740394] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], SUBCELLULAR LOCATION, TISSUE SPECIFICITY.
[4]	"Complete sequencing and characterization of 21,243 full-length human cDNAs." Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S. Nat. Genet. 36:40-45(2004) [PubMed: 14702039] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Hepatoma.
[5]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed: 15489334] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Brain, Pancreas and Testis.
[6]	"HsAtg4B/HsApg4B/autophagin-1 cleaves the carboxyl termini of three human Atg8 homologues and delipidates microtubule-associated protein light chain 3- and GABAA receptor-associated protein-phospholipid conjugates." Tanida I., Sou Y.-S., Ezaki J., Minematsu-Ikeguchi N., Ueno T., Kominami E. J. Biol. Chem. 279:36268-36276(2004) [PubMed: 15187094] [Abstract] Cited for: LIPIDATION, CLEAVAGE BY APG4B.
[7]	"Human light chain 3/MAP1LC3B is cleaved at its carboxyl-terminal Met121 to expose Gly120 for lipidation and targeting to autophagosomal membranes." Tanida I., Ueno T., Kominami E. J. Biol. Chem. 279:47704-47710(2004) [PubMed: 15355958] [Abstract] Cited for: CLEAVAGE, MUTAGENESIS OF GLY-120 AND LYS-122.
[8]	"LC3 conjugation system in mammalian autophagy." Tanida I., Ueno T., Kominami E. Int. J. Biochem. Cell Biol. 36:2503-2518(2004) [PubMed: 15325588] [Abstract] Cited for: REVIEW.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBLGenBankDDBJ

AF303888 mRNA. Translation: AAG23182.1.
AF183417 mRNA. Translation: AAG09686.1.
AF087871 mRNA. Translation: AAM10499.1.
AK025556 mRNA. Translation: BAB15169.1.
BC018634 mRNA. Translation: AAH18634.1.
BC041874 mRNA. Translation: AAH41874.1.
BC067797 mRNA. Translation: AAH67797.1.

IPI

IPI00220482.

RefSeq

NP_073729.1.

UniGene

Hs.356061

3D structure databases

PDBPDBe

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1V49	NMR	-	A	1-120	[»]
2ZJD	X-ray	1.56	A/C	1-125	[»]

ModBase

Search...

Protein-protein interaction databases

IntAct

Q9GZQ8. 14 interactions.

Proteomic databases

PRIDE

Q9GZQ8.

Genome annotation databases

Ensembl

ENSG00000140941. Homo sapiens. [Contig view]

GeneID

81631.

KEGG

hsa:81631.

Organism-specific databases

GeneCards

GC16P085982.

H-InvDB

HIX0013321.
HIX0035198.
HIX0059104.

HGNC

HGNC:13352. MAP1LC3B.

MIM

609604. gene.

PharmGKB

PA134923100.

GenAtlas

Search...

Phylogenomic databases

HOGENOM

Q9GZQ8.

HOVERGEN

Q9GZQ8.

OMA

Q9GZQ8. FKERRPF.

Gene expression databases

ArrayExpress

Q9GZQ8.

Bgee

Q9GZQ8.

CleanEx

HS_MAP1LC3B.

GermOnline

ENSG00000140941. Homo sapiens.

Family and domain databases

InterPro

IPR004241. MAP1_LC3.
[Graphical view]

PANTHER

PTHR10969. MAP1_LC3. 1 hit.

Pfam

PF02991. MAP1_LC3. 1 hit.
[Graphical view]

ProtoNet

Search...

Other Resources

NextBio

72018.

PMAP-CutDB

Q9GZQ8.

SOURCE

Search...

Entry information

Entry name

MLP3B_HUMAN

Accession

Primary (citable) accession number: Q9GZQ8
Secondary accession number(s): Q6NW02

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 5, 2001
Last sequence update:	January 23, 2007
Last modified:	June 16, 2009
This is version 83 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)