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Protein

Spectrin alpha chain, non-erythrocytic 1

Gene

SPTAN1

Organism
Gallus gallus (Chicken)
Status
Reviewed-Annotation score: Annotation score: 4 out of 5-Experimental evidence at protein leveli

Functioni

Morphologically, spectrin-like proteins appear to be related to spectrin, showing a flexible rod-like structure. They can bind actin but seem to differ in their calmodulin-binding activity. In nonerythroid tissues, spectrins, in association with some other proteins, may play an important role in membrane organization.

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Calcium bindingi2341 – 23521PROSITE-ProRule annotationAdd BLAST12
Calcium bindingi2384 – 23952PROSITE-ProRule annotationAdd BLAST12

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Actin capping

Keywords - Ligandi

Actin-binding, Calcium, Calmodulin-binding, Metal-binding

Names & Taxonomyi

Protein namesi
Recommended name:
Spectrin alpha chain, non-erythrocytic 1
Alternative name(s):
Alpha-II spectrin
Fodrin alpha chain
Gene namesi
Name:SPTAN1
Synonyms:SPTA2
OrganismiGallus gallus (Chicken)
Taxonomic identifieri9031 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiArchelosauriaArchosauriaDinosauriaSaurischiaTheropodaCoelurosauriaAvesNeognathaeGalloanseraeGalliformesPhasianidaePhasianinaeGallus
Proteomesi
  • UP000000539 Componenti: Unplaced

Subcellular locationi

GO - Cellular componenti

  • cell cortex Source: UniProtKB-SubCell
  • costamere Source: AgBase
  • cytoskeleton Source: UniProtKB-SubCell
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm, Cytoskeleton

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00000734541 – 2477Spectrin alpha chain, non-erythrocytic 1Add BLAST2477

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei1176PhosphotyrosineBy similarity1

Post-translational modificationi

Phosphorylation of Tyr-1176 decreases sensitivity to cleavage by calpain in vitro.By similarity

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sitei1176 – 1177Cleavage; by mu-calpainBy similarity2

Keywords - PTMi

Phosphoprotein

Proteomic databases

PaxDbiP07751.
PRIDEiP07751.

Interactioni

Subunit structurei

Like erythrocyte spectrin, the spectrin-like proteins are capable of forming dimers which can further associate to tetramers. Interacts with ACP1 (By similarity).By similarity

Protein-protein interaction databases

MINTiMINT-139133.
STRINGi9031.ENSGALP00000007504.

Structurei

Secondary structure

12477
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi967 – 969Combined sources3
Beta strandi971 – 974Combined sources4
Beta strandi981 – 984Combined sources4
Beta strandi993 – 998Combined sources6
Beta strandi1001 – 1009Combined sources9
Beta strandi1012 – 1017Combined sources6
Helixi1018 – 1020Combined sources3
Beta strandi1021 – 1023Combined sources3
Beta strandi1040 – 1043Combined sources4
Helixi1664 – 1686Combined sources23
Helixi1695 – 1730Combined sources36
Beta strandi1733 – 1735Combined sources3
Helixi1771 – 1791Combined sources21
Helixi1801 – 1837Combined sources37
Helixi1843 – 1898Combined sources56
Helixi1907 – 1944Combined sources38
Helixi1949 – 1981Combined sources33

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1AEYNMR-A965-1025[»]
1AJ3NMR-A1763-1872[»]
1BK2X-ray2.01A969-1025[»]
1CUNX-ray2.00A/B/C1770-1982[»]
1E6GX-ray2.30A965-1025[»]
1E6HX-ray2.01A965-1025[»]
1E7OX-ray3.20A965-1025[»]
1G2BX-ray1.12A967-1025[»]
1H8KX-ray2.70A965-1025[»]
1HD3X-ray1.98A965-1025[»]
1M8MNMR-A965-1025[»]
1NEGX-ray2.30A965-1024[»]
1PWTX-ray1.77A967-1025[»]
1QKWX-ray2.00A964-1025[»]
1QKXX-ray1.80A964-1025[»]
1SHGX-ray1.80A965-1025[»]
1TUCX-ray2.02A983-1026[»]
A1030-1090[»]
1TUDX-ray1.77A964-1010[»]
1U06X-ray1.49A965-1025[»]
1U4QX-ray2.50A/B1662-1982[»]
1U5PX-ray2.00A1662-1876[»]
1UUEX-ray2.60A965-1025[»]
2CDTX-ray2.54A965-1025[»]
2F2VX-ray1.85A965-1025[»]
2F2WX-ray1.70A965-1025[»]
2F2XX-ray1.60A965-1025[»]
2JM8NMR-A965-1025[»]
2JM9NMR-A965-1025[»]
2JMANMR-A965-1025[»]
2JMCNMR-A983-1025[»]
2KR3NMR-A965-1025[»]
2KXDNMR-A967-1025[»]
2LJ3NMR-A965-1025[»]
2NUZX-ray1.85A965-1025[»]
2OAWX-ray1.90A/B/C/D969-1025[»]
2RMONMR-A965-1025[»]
2ROTNMR-A965-1025[»]
3I9QX-ray1.45A969-1025[»]
3M0PX-ray2.60A965-1025[»]
3M0QX-ray1.75A965-1025[»]
3M0RX-ray1.10A965-1025[»]
3M0SX-ray1.60A969-1025[»]
3M0TX-ray1.70A965-1025[»]
3M0UX-ray1.10A965-1025[»]
3NGPX-ray1.08A965-1025[»]
4F16X-ray1.93A965-1025[»]
4F17X-ray1.55A965-1025[»]
ProteinModelPortaliP07751.
SMRiP07751.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP07751.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Repeati15 – 119Spectrin 1Add BLAST105
Repeati120 – 225Spectrin 2Add BLAST106
Repeati226 – 331Spectrin 3Add BLAST106
Repeati332 – 437Spectrin 4Add BLAST106
Repeati438 – 543Spectrin 5Add BLAST106
Repeati544 – 648Spectrin 6Add BLAST105
Repeati649 – 754Spectrin 7Add BLAST106
Repeati755 – 860Spectrin 8Add BLAST106
Repeati861 – 966Spectrin 9Add BLAST106
Domaini967 – 1026SH3PROSITE-ProRule annotationAdd BLAST60
Repeati1062 – 1167Spectrin 10Add BLAST106
Repeati1204 – 1309Spectrin 11Add BLAST106
Repeati1310 – 1415Spectrin 12Add BLAST106
Repeati1416 – 1521Spectrin 13Add BLAST106
Repeati1522 – 1633Spectrin 14Add BLAST112
Repeati1634 – 1739Spectrin 15Add BLAST106
Repeati1740 – 1845Spectrin 16Add BLAST106
Repeati1846 – 1951Spectrin 17Add BLAST106
Repeati1952 – 2058Spectrin 18Add BLAST107
Repeati2059 – 2171Spectrin 19Add BLAST113
Repeati2172 – 2256Spectrin 20Add BLAST85
Domaini2328 – 2363EF-hand 1PROSITE-ProRule annotationAdd BLAST36
Domaini2371 – 2406EF-hand 2PROSITE-ProRule annotationAdd BLAST36
Domaini2409 – 2444EF-hand 3PROSITE-ProRule annotationAdd BLAST36

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni1 – 14N-terminal domainAdd BLAST14
Regioni2257 – 2477C-terminal domainAdd BLAST221

Domaini

Spectrin-like proteins have five domains: (1) N-terminal domain (N), (2) domain between the N-terminal and middle domain (NM), (3) middle domain (M), (4) domain between the middle and C-terminal domain (MC), (5) C-terminal domain (C). NM and MC domains are composed of typical spectrin 106 residues repeats (1-8 for NM and 12-19 for MC) and are homologous to each other. N, M, and C domains are composed of sequences that do not form typical spectrin repeats.

Sequence similaritiesi

Belongs to the spectrin family.Curated
Contains 3 EF-hand domains.PROSITE-ProRule annotation
Contains 1 SH3 domain.PROSITE-ProRule annotation
Contains 20 spectrin repeats.Curated

Keywords - Domaini

Repeat, SH3 domain

Phylogenomic databases

eggNOGiKOG0035. Eukaryota.
COG5069. LUCA.
HOGENOMiHOG000246965.
HOVERGENiHBG059266.
InParanoidiP07751.
KOiK06114.
PhylomeDBiP07751.

Family and domain databases

CDDicd00051. EFh. 1 hit.
Gene3Di1.10.238.10. 2 hits.
InterProiIPR011992. EF-hand-dom_pair.
IPR014837. EF-hand_Ca_insen.
IPR018247. EF_Hand_1_Ca_BS.
IPR002048. EF_hand_dom.
IPR001452. SH3_domain.
IPR018159. Spectrin/alpha-actinin.
IPR013315. Spectrin_alpha_SH3.
IPR002017. Spectrin_repeat.
[Graphical view]
PfamiPF13499. EF-hand_7. 1 hit.
PF08726. EFhand_Ca_insen. 1 hit.
PF00018. SH3_1. 1 hit.
PF00435. Spectrin. 20 hits.
[Graphical view]
PRINTSiPR00452. SH3DOMAIN.
PR01887. SPECTRNALPHA.
SMARTiSM00054. EFh. 2 hits.
SM00326. SH3. 1 hit.
SM00150. SPEC. 20 hits.
[Graphical view]
SUPFAMiSSF47473. SSF47473. 1 hit.
SSF50044. SSF50044. 1 hit.
PROSITEiPS00018. EF_HAND_1. 2 hits.
PS50222. EF_HAND_2. 3 hits.
PS50002. SH3. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

P07751-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MDPSGVKVLE TAEDIQERRQ QVLDRYHRFK ELSSLRRQKL EDSYRFQFFQ
60 70 80 90 100
RDADELGKWI QEKLQIASDE NYKDPSNLQG KLQKHQAFEA EVQANSGAIV
110 120 130 140 150
KLDETGNQMI NEGHFASETI RTRLQELHRL WELLLEKMRE KGVKLLQAQK
160 170 180 190 200
LVQFLRECED VMDWINDKEA IVTSEELGQD LEHVEVLQKK FEEFQTDLAA
210 220 230 240 250
HEERVNEVNQ FAGKLIQEQH PEEELIKSKQ DEVNASWQRL KGLAQQRQGK
260 270 280 290 300
LFGAAEVQRF NRDVDETISW IKEKGQLMAS DDFGRDLASV QALLRKHEGL
310 320 330 340 350
ERDLAAFHHK VKALCAEADR LQQSHPINAS QIQVKREELI ANWEQIRTLA
360 370 380 390 400
AERHARLNDS YRLQRFLADF RDLTSWVTEM KALINADELA NDVAGAEALL
410 420 430 440 450
DRHQEHKGEI DAHEDSFRSA DESGQALLAA GHYASDEVKE KLTILSDERS
460 470 480 490 500
ALLELWELRR QQYEQCMDLQ LFYRDTEQVD NWMSKQEAFL LNEDLGDSLD
510 520 530 540 550
SVEALLKKHE DFEKSLSAQE EKITALDEFA TKLIQNNHYA MDDVATRRDA
560 570 580 590 600
LLSRRNALHE RAMKRRAQLA DSFHLQQFFR DSDELKSWVN EKMKTATDEA
610 620 630 640 650
YKDPSNLQGK VQKHQAFEAE LSANQSRIDA LEKAGQKLID VNHYASDEVA
660 670 680 690 700
ARMNEVISLW KKLLEATELK GIKLREANQQ QQFNRNVEDI ELWLYEVEGH
710 720 730 740 750
LASDDYGKDL TSVQNLQKKH ALLEADVAAH QDPIDGITIQ ARQFQDAGHF
760 770 780 790 800
DADNIKKKQE ALVARYEALK DPMVARKQKL ADSLRLQQLF RDIEDEETWI
810 820 830 840 850
REKEPIAAST NRGKDLIGVQ NLLKKHQALQ AEIAGHEPRI KAVTQKGNAM
860 870 880 890 900
VEEGHFAAED VKIKLNELNQ KWDSLKAKAS QRRQDLEDSL QAQQYFADAN
910 920 930 940 950
EAQSWMREKE PIVGSTDYGK DEDSAEALLK KHEALMSDLS AYGSSIQALR
960 970 980 990 1000
EQAQSCRQQV APTDDETGKE LVLALYDYQE KSPREVTMKK GDILTLLNST
1010 1020 1030 1040 1050
NKDWWKVEVN DRQGFVPAAY VKKLDPAQSA SRENLLEEQG SIALRQEQID
1060 1070 1080 1090 1100
NQTLITKEVG SVSLRMKQVE ELYHSLLELG EKRKGMLEKS CKKFMLFREA
1110 1120 1130 1140 1150
NELQQWINEK EAALTNEEVG ADLEQVEVLQ KKFDDFQKDL KANESRLKDI
1160 1170 1180 1190 1200
NKVANDLESE GLMAEEVQAV EHQEVYGMMP RDETDSKTVS PWKSARMMVH
1210 1220 1230 1240 1250
TVATFNSIKE LNERWRSLQQ LAEERSQLLG SADEVQRFHR DADETKEWIE
1260 1270 1280 1290 1300
EKNQALNTDN YGHDLASVQA LQRNDEGFER DLAALGDKVN SLGETAQRLI
1310 1320 1330 1340 1350
QSHPELAEDL QEKCTELNQA WSSLGKRADQ RKEKLGDSHD LQRFLSDFRD
1360 1370 1380 1390 1400
LMSWINGIRG LVSSDELAKD VTGAEALLER HQEHRTEIDA RAGTFQAFEQ
1410 1420 1430 1440 1450
FGQQLLARGH YASPEIKEKL DILDQERTDL EKAWVQRRMM LDQCLELQLF
1460 1470 1480 1490 1500
HRDCEQAENW MAAREAFLNT EDKGDSLDSV EALIKKHEDF DKAINVQEEK
1510 1520 1530 1540 1550
IAVLQSFADQ LIAADHYAKG VIANRRNEVL DRWRRLKAQM IEKRSKLGES
1560 1570 1580 1590 1600
QTLQQFSRDV DEIEAWISEK LQTASDESYK DPTNIQLSKL LSKHQKHQAF
1610 1620 1630 1640 1650
EAELHANADR IRGVIEMGNP LIERGACAGS EDAVKARLAA LADQWEFLVQ
1660 1670 1680 1690 1700
KSSEKSQKLK EANKQQNFNT GIKDFDFWLS EVEALLASED YGKDLASVNN
1710 1720 1730 1740 1750
LLKKHQLLEA DISAHEDRLK DLNSQADSLM TSSAFDTSQV KDKRETINGR
1760 1770 1780 1790 1800
FQRIKSMAAA RRAKLNESHR LHQFFRDMDD EESWIKEKKL LVSSEDYGRD
1810 1820 1830 1840 1850
LTGVQNLRKK HKRLEAELAA HEPAIQGVLD TGKKLSDDNT IGKEEIQQRL
1860 1870 1880 1890 1900
AQFVDHWKEL KQLAAARGQR LEESLEYQQF VANVEEEEAW INEKMTLVAS
1910 1920 1930 1940 1950
EDYGDTLAAI QGLLKKHEAF ETDFTVHKDR VNDVCANGED LIKKNNHHVE
1960 1970 1980 1990 2000
NITAKMKGLK GKVSDLEKAA AQRKAKLDEN SAFLQFNWKA DVVESWIGEK
2010 2020 2030 2040 2050
ENSLKTDDYG RDLSSVQTLL TKQETFDAGL QAFQQEGIAN ITALKDQLLA
2060 2070 2080 2090 2100
AKHIQSKAIE VRHASLMKRW NQLLANSAAR KKKLLEAQEH FRKVEDLFLT
2110 2120 2130 2140 2150
FAKKASAFNS WFENAEEDLT DPVRCNSLEE IKALREAHDA FRSSLSSAQA
2160 2170 2180 2190 2200
DFNQLAELDR QIKSFRVASN PYTWFTMEAL EETWRNLQKI IKERELELQK
2210 2220 2230 2240 2250
EQRRQEENDK LRQEFAQHAN AFHQWIQETR TYLLDGSCMV EESGTLESQL
2260 2270 2280 2290 2300
EATKRKHQEI RAMRSQLKKI EDLGAAMEEA LILDNKYTEH STVGLAQQWD
2310 2320 2330 2340 2350
QLDQLGMRMQ HNLEQQIQAR NTTGVTEEAL KEFSMMFKHF DKDKSGRLNH
2360 2370 2380 2390 2400
QEFKSCLRSL GYDLPMVEEG EPDPEFESIL DTVDPNRDGH VSLQEYMAFM
2410 2420 2430 2440 2450
ISRETENVKS SEEIESAFRA LSSERKPYVT KEELYQNLTR EQADYCISHM
2460 2470
KPYMDGKGRE LPSAYDYIEF TRSLFVN
Length:2,477
Mass (Da):285,363
Last modified:August 1, 1991 - v3
Checksum:iAD4C876994E6AB39
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X14518 Genomic DNA. Translation: CAA32662.1.
X14519 mRNA. Translation: CAA32663.1. Sequence problems.
X02593 mRNA. Translation: CAB51571.1. Sequence problems.
PIRiA30122. SJCHA.
RefSeqiNP_001036003.1. NM_001042538.1.
UniGeneiGga.11413.

Genome annotation databases

GeneIDi374234.
KEGGigga:374234.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X14518 Genomic DNA. Translation: CAA32662.1.
X14519 mRNA. Translation: CAA32663.1. Sequence problems.
X02593 mRNA. Translation: CAB51571.1. Sequence problems.
PIRiA30122. SJCHA.
RefSeqiNP_001036003.1. NM_001042538.1.
UniGeneiGga.11413.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1AEYNMR-A965-1025[»]
1AJ3NMR-A1763-1872[»]
1BK2X-ray2.01A969-1025[»]
1CUNX-ray2.00A/B/C1770-1982[»]
1E6GX-ray2.30A965-1025[»]
1E6HX-ray2.01A965-1025[»]
1E7OX-ray3.20A965-1025[»]
1G2BX-ray1.12A967-1025[»]
1H8KX-ray2.70A965-1025[»]
1HD3X-ray1.98A965-1025[»]
1M8MNMR-A965-1025[»]
1NEGX-ray2.30A965-1024[»]
1PWTX-ray1.77A967-1025[»]
1QKWX-ray2.00A964-1025[»]
1QKXX-ray1.80A964-1025[»]
1SHGX-ray1.80A965-1025[»]
1TUCX-ray2.02A983-1026[»]
A1030-1090[»]
1TUDX-ray1.77A964-1010[»]
1U06X-ray1.49A965-1025[»]
1U4QX-ray2.50A/B1662-1982[»]
1U5PX-ray2.00A1662-1876[»]
1UUEX-ray2.60A965-1025[»]
2CDTX-ray2.54A965-1025[»]
2F2VX-ray1.85A965-1025[»]
2F2WX-ray1.70A965-1025[»]
2F2XX-ray1.60A965-1025[»]
2JM8NMR-A965-1025[»]
2JM9NMR-A965-1025[»]
2JMANMR-A965-1025[»]
2JMCNMR-A983-1025[»]
2KR3NMR-A965-1025[»]
2KXDNMR-A967-1025[»]
2LJ3NMR-A965-1025[»]
2NUZX-ray1.85A965-1025[»]
2OAWX-ray1.90A/B/C/D969-1025[»]
2RMONMR-A965-1025[»]
2ROTNMR-A965-1025[»]
3I9QX-ray1.45A969-1025[»]
3M0PX-ray2.60A965-1025[»]
3M0QX-ray1.75A965-1025[»]
3M0RX-ray1.10A965-1025[»]
3M0SX-ray1.60A969-1025[»]
3M0TX-ray1.70A965-1025[»]
3M0UX-ray1.10A965-1025[»]
3NGPX-ray1.08A965-1025[»]
4F16X-ray1.93A965-1025[»]
4F17X-ray1.55A965-1025[»]
ProteinModelPortaliP07751.
SMRiP07751.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

MINTiMINT-139133.
STRINGi9031.ENSGALP00000007504.

Proteomic databases

PaxDbiP07751.
PRIDEiP07751.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

GeneIDi374234.
KEGGigga:374234.

Organism-specific databases

CTDi6709.

Phylogenomic databases

eggNOGiKOG0035. Eukaryota.
COG5069. LUCA.
HOGENOMiHOG000246965.
HOVERGENiHBG059266.
InParanoidiP07751.
KOiK06114.
PhylomeDBiP07751.

Miscellaneous databases

EvolutionaryTraceiP07751.
PROiP07751.

Family and domain databases

CDDicd00051. EFh. 1 hit.
Gene3Di1.10.238.10. 2 hits.
InterProiIPR011992. EF-hand-dom_pair.
IPR014837. EF-hand_Ca_insen.
IPR018247. EF_Hand_1_Ca_BS.
IPR002048. EF_hand_dom.
IPR001452. SH3_domain.
IPR018159. Spectrin/alpha-actinin.
IPR013315. Spectrin_alpha_SH3.
IPR002017. Spectrin_repeat.
[Graphical view]
PfamiPF13499. EF-hand_7. 1 hit.
PF08726. EFhand_Ca_insen. 1 hit.
PF00018. SH3_1. 1 hit.
PF00435. Spectrin. 20 hits.
[Graphical view]
PRINTSiPR00452. SH3DOMAIN.
PR01887. SPECTRNALPHA.
SMARTiSM00054. EFh. 2 hits.
SM00326. SH3. 1 hit.
SM00150. SPEC. 20 hits.
[Graphical view]
SUPFAMiSSF47473. SSF47473. 1 hit.
SSF50044. SSF50044. 1 hit.
PROSITEiPS00018. EF_HAND_1. 2 hits.
PS50222. EF_HAND_2. 3 hits.
PS50002. SH3. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiSPTN1_CHICK
AccessioniPrimary (citable) accession number: P07751
Entry historyi
Integrated into UniProtKB/Swiss-Prot: August 1, 1988
Last sequence update: August 1, 1991
Last modified: November 30, 2016
This is version 152 of the entry and version 3 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  2. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.