Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
2  structures 1210  species 0  interactions 2241  sequences 59  architectures

Family: Intu_longin_1 (PF19031)

Summary: First Longin domain of INTU, CCZ1 and HPS4

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

The Pfam group coordinates the annotation of Pfam families in Wikipedia, but we have not yet assigned a Wikipedia article to this family. If you think that a particular Wikipedia article provides good annotation, please let us know.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

First Longin domain of INTU, CCZ1 and HPS4 Provide feedback

This entry is specific to the first Longin domain of the HerMon (Hermansky-Pudlak syndrome and MON1/CCZ1) family, including protein sequences of INTU, CCZ1 and HPS4 families [1,3,5]. The Mon1/Ccz1 complex (MC1) is the GDP/GTP exchange factor (GEF) for the Rab GTPase Ypt7/Rab7 during vesicular trafficking [2]. The Hps1/Hps4 complex (BLOC-3) is a Rab32 and Rab38 GEF and is required for biogenesis of melanosomes and platelet dense granules [3]. Inturned (INTU) and Fuzzy (FUZ) proteins interact as members of the ciliogenesis and planar polarity effector (CPLANE) complex that controls recruitment of intraflagellar transport machinery to the basal body of primary cilia [4,6].

Literature references

  1. Kinch LN, Grishin NV; , Protein Sci. 2006;15:2669-2674.: Longin-like folds identified in CHiPS and DUF254 proteins: vesicle trafficking complexes conserved in eukaryotic evolution. PUBMED:17075139 EPMC:17075139

  2. Kiontke S, Langemeyer L, Kuhlee A, Schuback S, Raunser S, Ungermann C, Kummel D;, Nat Commun. 2017;8:14034.: Architecture and mechanism of the late endosomal Rab7-like Ypt7 guanine nucleotide exchange factor complex Mon1-Ccz1. PUBMED:28051187 EPMC:28051187

  3. Gerondopoulos A, Langemeyer L, Liang JR, Linford A, Barr FA;, Curr Biol. 2012;22:2135-2139.: BLOC-3 mutated in Hermansky-Pudlak syndrome is a Rab32/38 guanine nucleotide exchange factor. PUBMED:23084991 EPMC:23084991

  4. Gray RS, Abitua PB, Wlodarczyk BJ, Szabo-Rogers HL, Blanchard O, Lee I, Weiss GS, Liu KJ, Marcotte EM, Wallingford JB, Finnell RH;, Nat Cell Biol. 2009;11:1225-1232.: The planar cell polarity effector Fuz is essential for targeted membrane trafficking, ciliogenesis and mouse embryonic development. PUBMED:19767740 EPMC:19767740

  5. Sanchez-Pulido L, Ponting CP;, Bioinformatics. 2019 Sep 28. pii: 5575; [Epub ahead of print]: Hexa-Longin domain scaffolds for inter-Rab signalling. PUBMED:31562761 EPMC:31562761

  6. Toriyama M, Lee C, Taylor SP, Duran I, Cohn DH, Bruel AL, Tabler JM, Drew K, Kelly MR, Kim S, Park TJ, Braun DA, Pierquin G, Biver A, Wagner K, Malfroot A, Panigrahi I, Franco B, Al-Lami HA, Yeung Y, Choi YJ, Duffourd Y, Faivre L, Riviere JB, Chen J, Liu KJ, Marcotte EM, Hildebrandt F, Thauvin-Robinet C, Krakow D, Jackson PK, Wallingford JB;, Nat Genet. 2016;48:648-656.: The ciliopathy-associated CPLANE proteins direct basal body recruitment of intraflagellar transport machinery. PUBMED:27158779 EPMC:27158779

This tab holds annotation information from the InterPro database.

InterPro entry IPR043987

Longin domains are evolutionarily conserved regions widely distributed among eukaryotes, involved in membrane dynamic regulation and exhibit similarities in primary sequence and secondary structure. Longin-like domains are found in FUZ and related proteins, such as the MON1 and HPS1 proteins [ PUBMED:17075139 , PUBMED:23084991 , PUBMED:31562761 ]. The MON1/CCZ1 complex (MC1) is the GDP/GTP exchange factor (GEF) for the Rab GTPase Ypt7/Rab7 during vesicular trafficking [ PUBMED:28051187 ]. The HPS1/HPS4 complex (BLOC-3) is a Rab32 and Rab38 GEF and is required for biogenesis of melanosomes and platelet dense granules [ PUBMED:23084991 ]. Inturned (INTU) and Fuzzy (FUZ) proteins interact as members of the ciliogenesis and planar polarity effector (CPLANE) complex that controls recruitment of intraflagellar transport machinery to the basal body of primary cilia [ PUBMED:19767740 , PUBMED:27158779 ]. Structurally, these domains are composed of an alpha/beta fold which contains five anti-parallel beta-strands organised as a central beta-sheet and around it, two alpha-helices [ PUBMED:31562761 ].

This entry represents the first Longin domain found in INTU, CCZ1 and HPS4.

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

Loading domain graphics...

Pfam Clan

This family is a member of clan PF (CL0431), which has the following description:

The families here all show the Profilin-like fold, and represent both the Profilin (actin-binding protein) (55770) and the Roadblock/LC7 domain-type (103196) superfamilies.

The clan contains the following 21 members:

Clat_adaptor_s FNIP_N Fuz_longin_1 Fuz_longin_2 Fuz_longin_3 Intu_longin_1 Intu_longin_2 Intu_longin_3 LAMTOR5 Longin Longin_2 MAPKK1_Int Nyv1_N Profilin Robl_LC7 Sedlin_N SLM4 SRP-alpha_N SRX Sybindin uDENN


We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

View options

We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

Representative proteomes UniProt
Jalview View  View  View  View  View  View  View 
HTML View  View           
PP/heatmap 1 View           

1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: ✓ available, x not generated, not available.

Format an alignment

Representative proteomes UniProt

Download options

We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

Representative proteomes UniProt
Raw Stockholm Download   Download   Download   Download   Download   Download   Download  
Gzipped Download   Download   Download   Download   Download   Download   Download  

You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

HMM logo

HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...


This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

Note: You can also download the data file for the tree.

Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Luis Sanchez-Pulido
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Bateman A
Number in seed: 37
Number in full: 2241
Average length of the domain: 118.20 aa
Average identity of full alignment: 22 %
Average coverage of the sequence by the domain: 17.76 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 23.7 23.7
Trusted cut-off 23.8 23.7
Noise cut-off 23.6 23.6
Model length: 113
Family (HMM) version: 2
Download: download the raw HMM for this family

Species distribution

Sunburst controls


Weight segments by...

Change the size of the sunburst


Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


Align selected sequences to HMM

Generate a FASTA-format file

Clear selection

This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

Loading sunburst data...

Tree controls


The tree shows the occurrence of this domain across different species. More...


Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.


For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Intu_longin_1 domain has been found. There are 2 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

Loading structure mapping...