Microsporidia are a large group of mysterious obligate intracellular eukaryotic parasites. The microsporidian spore can survive in the absence of nutrients for years under harsh conditions and germinate within seconds under the stimulation of environmental changes like pH and ions. During germination, microsporidia experience an increase in intrasporal osmotic pressure, which leads to an influx of water into the spore, followed by swelling of the polaroplasts and posterior vacuole, which eventually fires the polar filament (PF). Infectious sporoplasm was transported through the extruded polar tube (PT) and delivered into the host cell.
Species | Protein/UniProtKB | Number of Amino Acids | PI | Mainly Location | Features | Mw (kDa) | References |
---|---|---|---|---|---|---|---|
Encephalitozoon cuniculi | EcSWP1/Q9XZV1 | 450 | 4.96 | Exospore | glycine- and serine-rich repeats | 51 | Bohne et al., 2000 [60][30] |
EcEnP1/Q8SWL3 | 357 | 9.07 | Endospore | HBM | 40.5 | Southern et al., 2007 [61][31] Peuvel et al., 2006 [62][32] |
|
EcEnP2/EcSWP3/Q8SWI4 | 221 | 8.42 | Endospore | glycosylphosphatidylinositol (GPI) anchored and O-glycosylation sites | 22 | Peuvel et al., 2007 [62][32] Xu et al., 2006 [63][33] |
|
EcCDA/Q8SU65 | 254 | 4.43 | Endospore,plasma membrane | Glycoside hydrolase and deacetylase | 28.1 | Brosson et al., 2005 [64][34] | |
Encephalitozoon intestinalis | EiSWP1/Q95WA3 | 388 | 4.78 | Exospore | - | 41 | Hayman et al., 2001 [65][35] |
EiSWP2/Q95WA4 | 1002 | 3.68 | Exospore | Repeating of amino-acid units | 107 | Hayman et al., 2001 [65][35] | |
EiEnP1/A7TZU4 | 348 | 8.84 | Exospore,endospore and polar membrane layer | HBM | 39.1 | Southern et al., 2007 [61][31] | |
Encephalitozoon hellem | EhSWP1a/C3VJR1 | 509 | 4.30 | Exospore | - | 55 | Polonais et al., 2010 [66][36] |
EhSWP1b/C3VJR2 |
Species | Protein/UniProtKB | Number of Amino Acids | Features | Mw(kDa) | References | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Encephalitozoon cuniculi | EcPTP1/O76942 | 395 | Acidic proline-rich, hydrophobicity, presence of tandem repeats, mannosylated with O-glycosylation, signal peptide, interact with the Concanavalin A (ConA), localized on the whole PT | 37 | Xu et al., 2004 [113][89] Bouzahzah et al., 2010 [114][90] Delbac et al., 1998 [125][103] |
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EcPTP2/Q8SRT0 | 277 | Basic lysine-rich core, acidic tail, can form intermolecular disulfide bridges with PTP1, RGD motif and signal peptide, localized on the whole PT | 30 | Delbac et al., 2001 [111][87] Peuvel et al., 2002 [116][92] |
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EcPTP3/Q8MTP3 | 1256 | Acidic core flanked by highly basic N- and C-termini, lacks cysteine residue, may assist in controlling PT extrusion, signal peptide, localized on the whole PT | 150 | Peuvel et al., 2002 [116][92] | |||||||||
Encephalitozoon intestinalis | EiPTP1/Q5F2J0 | 371 | proline-rich, presence of tandem repeats, absent tryptophan and arginine, O-glycosylation and signal peptide, interact with the ConA, localized to polar filaments | 35 | Bouzahzah et al., 2010 [114][90] Peuvel et al., 2002 [116][92] |
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EiPTP2/P0CAT4 | 275 | lysine-rich, RGD motif, N-glycosylation and signal peptide | 30 | Peuvel et al., 2002 [116][92] | |||||||||
Encephalitozoon hellem | EhPTP1/O76273 | 453 | proline-rich, presence of tandem repeats, mannosylated with N-, O-glycosylation, absent tryptophan and arginine, signal peptide, interact with the ConA, localized to polar filaments | 43 | Keohane et al., 1998 [110][86] Xu et al., 2004 [113][89] Peuvel et al., 2002 [116][92], |
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EhPTP2/P0CAT5 | 272 | lysine-rich, N-glycosylation, RGN motif and signal peptide, localized on the whole polar | 30 | Peuvel et al., 2002 [116][92] | |||||||||
EhPTP4/I6UDI1 | 278 | signal peptide, located at the tip of the PT, N-, O-glycosylation | 36 | Han et al., 2017 [22][94] | |||||||||
533 | 4.64 | Exospore | - | 60 | Polonais et al., 2010 | ||||||||
Nosema bombycis | NbPTP1/R0MQM8 | [ | 409 | signal peptide, O-glycosylation, phosphorylation, localized on the whole PT | 55 | Wu et al., 2014 [126][104] | 66][36] | ||||||
Nosema bombycis | NbSWP1/B3STN5 | 278 | 7.95 | ||||||||||
NbPTP2/R0KY97 | 277 | PI = 9.39, signal peptide, interacted with SWP5, presence in the whole polor tube, phosphorylation, localized on the whole PT | Endospore | - | 30.4 | 39 | Li et al., 2012 [67][37] Wang et al., 2007 [127][105] Yi et al., 2019 [128][Wu et al., 2008 [45][11] |
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106 | ] | NbSWP2/B3STN6 | 268 | 8.45 | |||||||||
NbPTP3/J7EQ15 | 1370 | Endospore | PI = 6.73, interacted with SWP5, localized on the whole PT | HBM | 150 | Li et al., 2012 [67][37] Wang et al., 2007 [25.3 |
127][105]Wu et al., 2008 [45][11] | ||||||
NbSWP3/B3STN7 | 316 | ||||||||||||
NbPTP4/- | 7.29 | Exospore | 222 | PI = 7.56, located at the front end of the PT and around the anchor disk, interact with Bmtubulin-α | 25.3- | Liu, 2019 32.7 | [129][Wu et al., 2008 [45][11] | ||||||
107 | ] | NbSWP5/G0Z414 | 186 | 4.39 | Endospore and PT | ||||||||
NbPTP5/R0KWI6 | Interacts with PTP2 and PTP3 | 20.3 | Li et al., 2012 | 271 | [ | PI = 8.68, located at the front end of the PT and around the anchor disk | 32.5 | Liu, 2019 [129][107]67,68][37][38] | |||||
NbSWP7/B3STP1 | 287 | 4.78 | Exospore and endospore | Interacts with NbSWP9 | 32.8 | Yang et al., 2015 [69][39] | |||||||
NbPTP6/R0MBR8 | 247 | rich in histidine (H) and serine (S), signal peptide, N-, O-glycosylation, cell-binding ability, localized on the whole PT | 28.3 | Lv et al., 2020 [117][95] | NbSWP9/R0MLT0 | 367 | 8.32 | Exospore, endospore and PT | |||||
NbSWP5/B3STN9 | 186 | PI = 4.39, localized to the exospore and the region of the PT, interacts with the PT proteins NbPTP2 and NbPTP3 | Interacts with PTP1, PTP2 and NbSWP9 | 42.8 | Yang et al., 2015 | [69][39] | |||||||
20.3 | Li et al., 2012 | [ | 67 | , | 68][37][38] | NbSWP11/B3STP5 | 446 | 9.27 | Exospore and endospore | DnaJ domain and HBM | 52.3 | Yang et al., 2014 [70][40] | |
NbSWP7/B3STP1 | 287 | PI = 4.78, located in the PT and spore wall. | 32.8 | Yang et al., 2015 [69][39] | NbSWP12/B3STP6 | 228 | 6.78 | Exospore, endospore, membrane of meront | BAR-2 domain and HBM | 26.6 | |||
NbSWP9/R0MLT0 | Chen et al., 2013 | 367 | PI = 8.92, located in the spore wall, as well as anchoring disk and the front end of the PT after germination; interacts with NbPTP1 and NbPTP2 | 42.8 | Yang et al., 2015 [69][39] | [71,72,73][41][42][43] | |||||||
NbSWP16/R0MN98 | 211 | 8.42 | Exospore | HBM and proline-rich tandem repeats | 44 | Wang et al., 2015 [ | |||||||
Enterocytozoon hepatopenaei | EhpPTP2/A0A1W0E7X7 | 284 | 74 | PI = 8.8, rich in lysine, super family domain (pfam17022), O-glycosylation | ] | [ | 3244] | ||||||
Wang et al., 2021 | [ | 130 | ] | [ | 108] | NbSWP26/B9UJ97 | 223 | 5.09 | Exospore | HBM and N-glycosylation sites | |||
Antonospora locustae | 25.7 | (formerly Nosema locustae) | Li et al., 2009 | [ | 75 | ] | [45] | ||||||
AlPTP1/- | 355 | PI = 5.2, rich in proline and glycine, N-, O-glycosylation, interact with the ConA, localized on the whole PT | 34 | Polonais et al., 2005 | [131 | Unnamed/EOB13250 | 244 | 10.24 | Endospore | Transmembrane domain | 28 | Wang et al., 2020 [76][46] | |
Nosema ceranae | Unnamed/A0A0F9WE74 | 226 | 6.84 | Endospore | - | 26.19 | Liang et al., 2021 [77][47] | ||||||
NcSWP8/A0A0F9WIV3 | 172 | 4.00 | - | Promote proliferation | 19.5 | He et al., 2021 [78][48] | |||||||
NcSWP12/A0A0F9WTX8 | 229 | 7.88 | - | Promote proliferation | 26.7 | He et al., 2021 [78][48] | |||||||
] | [ | 109 | ] | ||||||||||
AlPTP2/C8CG41 | 287 | PI = 9.1, signal peptide, O-glycosylation, rich in lysine, localized on the whole PT | 29 | Polonais et al., 2005 [131][109], | |||||||||
AlPTP2b/C8CG42 | 568 | signal peptide, PI = 8.4, O-glycosylation, rich glycine and serine, b-turn structures, localized on the whole PT | 55 | Polonais et al., 2013 [132][110] | |||||||||
AlPTP2c/C8CG43 | 599 | signal peptide, PI = 8.7, O-glycosylation, rich glycine and serine, b-turn structures | 56 | Polonais et al., 2013 [132][110] | |||||||||
Paranosema grylli | PgPTP1/- | 351 | PI = 5.2, acidic and proline-rich, N-glycosylation, interact with the ConA | 33 | Polonais et al., 2005 [131][109 | Enterocytozoon hepatopenaei | EhSWP1/A0A1W0E3P7 | 228 | 8.45 | Exospore and endospore | Exospore and endospore | 27 | Jaroenlak et al., 2018 [79][49] |
EhSWP2/A0A1W0E3S3 | 228 | 5.12 | - | MICSWaP domains | 25.7 | Li et al., 2021 [80][50] | |||||||
EhSWP3/A0A1W0E914 | 249 | Exospore and endospore | transmembrane domains | 27.1 | Fan et al., 2022 [81][51] | ||||||||
] | |||||||||||||
PgPTP2/- | 287 | PI = 8.9, rich in lysine | 29 | Polonais et al., 2005 [131][109] | |||||||||
Nosema pernyi | NpPTP1/A0A482G4U9 | 394 | PI = 5.82, signal peptide | 39.16 | Wang et al., 2019 [133][111] |
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NpPTP2/A0A482G3T3 | 277 | PI = 9.39, signal peptide | 30.8 | Wang et al., 2019 [133][111] |
EhSWP7/A0A1W0E705 | 250 | 5.04 | - | - | ||||
NpPTP3/A0A0N7ABT9 | 1370 | PI = 6.52, localized on the whole polar | 148.56 | Wang et al., 2019 [133 | 25.3 | ][111]Li et al., 2021 [80][50] | |||||||
EhEnp1/A0A1W0E696 | 333 | 8.86 | - | - | 38.3 | Li et al., 2021 [80][50] | |||||||
Antonospora locustae (formerly Nosema locustae) | AlocSWP2/A0A1W0E3S3 | 222 | 5.16 | Exospore and endospore | HBM | 25 | Chen et al., 2017 [82][52] | ||||||
EbSWP1/B7XHM5 | 228 | 7.06 | - | O-linked glycosylation site | 26.8 | Meng et al., 2022 [83][53] | |||||||
Enterocytozoon bieneusi | EbSWP2/B7XJH4 | 247 | 9.46 | - | N-linked glycosylation sites | 29.2 | Meng et al., 2022 [83][53] | ||||||
EbSWP3/B7XHL8 | 229 | 5.15 | - | N-linked glycosylation sites | 25.9 | Meng et al., 2022 [83][53] | |||||||
NpSWP1/A0A060A4C2 | 278 | 7.02 | Endospore | Transmembrane | 32 | Zhu et al., 2014 [84][54] | |||||||
Nosema pernyi | NpSWP9/A0A0N7AC01 | 317 | 5.75 | - | - | 37.16 | Ma et al., 2017 [85][55] | ||||||
NpSWP12/A0A0S2EGT8 | 228 | 5.96 | - | BAR domain | 26.6 | Feng et al., 2015 [86][56] | |||||||
Nosema antheraeae | NaSWP8/G3CU65 | 161 | 4.802 | - | HBM | 18.4 | Xi et al., 2010 [87][57] |