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5  structures 114  species 0  interactions 125  sequences 2  architectures

Family: Nro1 (PF12753)

Summary: Nuclear pore complex subunit Nro1

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Nuclear pore complex subunit Nro1 Provide feedback

In fission yeast, this protein is a positive regulator of the stability of Sre1N, the sterol regulatory element-binding protein which is an ER membrane-bound transcription factor that controls adaptation to low oxygen-growth [1]. In addition, the fission yeast Nro1 is a direct inhibitor of a protein that inhibits SreN1 degradation, Ofd1 (an oxoglutamate deoxygenase). The outcome of this reactivity is that Ofd1 acts as an oxygen sensor that regulates the binding of Nro1 to Ofd1 to control the stability of Sre1N [2]. Solution of the structure of Nro1 reveals it to be made up of a number of TPR coils [3]. TPR proteins are composed of three to 16 tandem peptide repeat motifs of 34 amino acids with degenerate sequence. The helical pairs adopt a helix-turn-helix anti-parallel arrangement with interacting helices. In general, TPR motifs are stacked together so that helix A from TPRn is packed between helix B from TPRn and helix A from TPRn+1. In Nro1, the 12 alpha helices forming the six TPR motifs are organised as follows from N terminus to C terminus - TPR1A, TPR1B, TPR2A, TPR2B, TPR3A, TPR3B, TPR4A, TPR4B, TPR5A, TPR5B, TPR6A, and TPR6B with the C-terminal helix (hC) running above the sixth TPR motif with an angle of approx 45 degrees with TPR6A and TPR6B. The corresponding TPRs structural motifs are longer (50 residues) than are canonical ones (34 amino acids) and are organised into two subdomains - Nro1-N (residues 55-225) and Nro1-C (residues 226-393). The Nro1/Etti protein plays a role in nuclear import suggesting that it is residues 4-19 that are interacting with Ofd1 [3].

Literature references

  1. Rout MP, Aitchison JD, Suprapto A, Hjertaas K, Zhao Y, Chait BT;, J Cell Biol. 2000;148:635-651.: The yeast nuclear pore complex: composition, architecture, and transport mechanism. PUBMED:10684247 EPMC:10684247

  2. Lee CY, Stewart EV, Hughes BT, Espenshade PJ;, EMBO J. 2009;28:135-143.: Oxygen-dependent binding of Nro1 to the prolyl hydroxylase Ofd1 regulates SREBP degradation in yeast. PUBMED:19158663 EPMC:19158663

  3. Rispal D, Henri J, van Tilbeurgh H, Graille M, Seraphin B;, RNA. 2011; [Epub ahead of print]: Structural and functional analysis of Nro1/Ett1: a protein involved in translation termination in S. cerevisiae and in O2-mediated gene control in S. pombe. PUBMED:21610214 EPMC:21610214

This tab holds annotation information from the InterPro database.

InterPro entry IPR024318

In fission yeast, Nro1 is a positive regulator of the stability of Sre1N, the sterol regulatory element-binding protein, which is an ER membrane-bound transcription factor that controls adaptation to low oxygen-growth [ PUBMED:10684247 ]. In addition, the fission yeast Nro1 is a direct inhibitor of a protein that inhibits SreN1 degradation, Ofd1 (an oxoglutamate deoxygenase). The outcome of this reactivity is that Ofd1 acts as an oxygen sensor that regulates the binding of Nro1 to Ofd1 to control the stability of Sre1N [ PUBMED:19158663 ].

This entry also represents ETT1, an Nro1 ortholog [ PUBMED:21610214 ]. ETT1 is required for correct translation termination and probably involved in regulation of hypoxic gene expression in association TPA1 [ PUBMED:20630870 ]. It inhibits replication of Brome mosaic virus [ PUBMED:14671320 ].

Gene Ontology

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Domain organisation

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Pfam Clan

This family is a member of clan TPR (CL0020), which has the following description:

Tetratricopeptide-like repeats are found in a numerous and diverse proteins involved in such functions as cell cycle regulation, transcriptional control, mitochondrial and peroxisomal protein transport, neurogenesis and protein folding.

The clan contains the following 176 members:

Adaptin_N Alkyl_sulf_dimr ANAPC3 ANAPC5 ANAPC8 APC_rep API5 Arm Arm_2 Arm_3 Arm_vescicular Atx10homo_assoc B56 BAF250_C BTAD CAS_CSE1 ChAPs CHIP_TPR_N CID CLASP_N Clathrin Clathrin-link Clathrin_H_link Clathrin_propel Cnd1 Cnd3 Coatomer_E Cohesin_HEAT Cohesin_load ComR_TPR COPI_C CPL CRM1_C CRM1_repeat CRM1_repeat_3 Cse1 CTK3 DHR-2 DIL DNA_alkylation Dopey_N Drf_FH3 Drf_GBD DUF1822 DUF2019 DUF2225 DUF3385 DUF3458_C DUF3808 DUF3856 DUF4042 DUF5588 DUF5691 DUF6340 DUF6377 DUF924 EAD11 EST1 EST1_DNA_bind FAT Fis1_TPR_C Fis1_TPR_N Foie-gras_1 GUN4_N HAT HEAT HEAT_2 HEAT_EZ HEAT_PBS HEAT_UF HemY_N HrpB1_HrpK HSM3_C HSM3_N IBB IBN_N IFRD Importin_rep Importin_rep_2 Importin_rep_3 Importin_rep_4 Importin_rep_5 Importin_rep_6 Insc_C KAP Leuk-A4-hydro_C LRV LRV_FeS MA3 MIF4G MIF4G_like MIF4G_like_2 MMS19_C Mo25 MRP-S27 Mtf2 NARP1 Neurochondrin Nipped-B_C Nro1 NSF Paf67 ParcG PC_rep PHAT PI3Ka PknG_TPR PPP5 PPR PPR_1 PPR_2 PPR_3 PPR_long PPTA Proteasom_PSMB PUF Rapsyn_N RIX1 RNPP_C RPM2 RPN7 Sel1 SHNi-TPR SNAP SPO22 SRP_TPR_like ST7 Suf SusD-like SusD-like_2 SusD-like_3 SusD_RagB SYCP2_ARLD TAF6_C TAL_effector TAtT Tcf25 TIP120 TOM20_plant TPR_1 TPR_10 TPR_11 TPR_12 TPR_14 TPR_15 TPR_16 TPR_17 TPR_18 TPR_19 TPR_2 TPR_20 TPR_21 TPR_22 TPR_3 TPR_4 TPR_5 TPR_6 TPR_7 TPR_8 TPR_9 TPR_MalT TTC7_N UNC45-central Upf2 V-ATPase_H_C V-ATPase_H_N Vac14_Fab1_bd Vitellogenin_N Vps39_1 W2 WSLR Wzy_C_2 Xpo1 YcaO_C YfiO Zmiz1_N


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Curation and family details

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Curation View help on the curation process

Seed source: Pfam-B_4826 (release 24.0)
Previous IDs: none
Type: Repeat
Sequence Ontology: SO:0001068
Author: Wood V , Coggill P
Number in seed: 12
Number in full: 125
Average length of the domain: 328.20 aa
Average identity of full alignment: 26 %
Average coverage of the sequence by the domain: 84.65 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild --amino -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 26.5 26.5
Trusted cut-off 27.0 27.7
Noise cut-off 26.0 26.4
Model length: 422
Family (HMM) version: 9
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Species distribution

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Archea Archea Eukaryota Eukaryota
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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 Nro1 domain has been found. There are 5 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.

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AlphaFold Structure Predictions

The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.

Protein Predicted structure External Information
Q08421 View 3D Structure Click here
Q5A0J9 View 3D Structure Click here
Q9USJ7 View 3D Structure Click here