Abstract
Main conclusion
Actin polarization and actin-driven host nuclear movement towards the fungal penetration site facilitates successful host colonization during compatible pea- Erysiphe pisi interactions.
Abstract
Proper nuclear positioning in plant cells is crucial for developmental processes and response to (a)biotic stimuli. During plant-fungal interactions, the host nucleus moves toward the infection site, a process regulated by the plant cytoskeleton. Notably, rearrangement of the plant cytoskeleton is one of the earliest cellular responses to pathogen invasion and is known to impact penetration efficiency. Yet, the connection between host nuclear movement and fungal ingress is still elusive, particularly in legumes. Here, we investigated the host nuclear dynamics during compatible interactions between Pisum sativum (pea) and the adapted powdery mildew (PM) fungus Erysiphe pisi to gain insights into the functional relevance of PM-induced nuclear movement in legumes. We show that the host nucleus moves towards the fungal appressorium before penetration and becomes associated with the primary haustorium. However, the nucleus migrates away from the primary infection site as the infection progresses toward colony expansion and sporulation. Treatment of pea leaves with the actin-polymerization inhibitor, cytochalasin D, abolished host nuclear movement towards the fungal penetration site and restricted PM growth. In contrast, treatment with oryzalin, a microtubule-polymerization inhibitor, had no effect. In addition to nuclear movement, strong polarization of host actin filaments towards the site of appressorial contact was evident at early infection stages. Our results suggest that actin focusing mediates host nuclear movement to the fungal penetration site and facilitates successful colonization during compatible pea-PM interactions.
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Data availability
All data generated or analyzed during this study are included in this published article [and its supplementary information files].
Abbreviations
- AF:
-
Actin filaments
- AMF:
-
Arbuscular mycorrhizal fungi
- AP:
-
Appressorium
- Bgh :
-
Blumeria graminis f.sp. hordei
- DAPI:
-
4′,6-Diamidino-2-phenylindole
- DMSO:
-
Dimethyl sulphoxide
- hpi:
-
Hours postinoculation
- LINC:
-
Linker of nucleoskeleton and cytoskeleton
- PH:
-
Primary hypha
- PI:
-
Propidium iodide
- PM:
-
Powdery mildew
- PPA:
-
Prepenetration apparatus
- SA:
-
Salicylic acid
- SH:
-
Secondary hypha
- SUN:
-
Sad1/Unc84
References
Baluška F, Bacigálová K, Oud JL et al (1995) Rapid reorganization of microtubular cytoskeleton accompanies early changes in nuclear ploidy and chromatin structure in postmitotic cells of barley leaves infected with powdery mildew. Protoplasma 185:140–151. https://doi.org/10.1007/BF01272854
Clark JIM, Hall JL (1998) Solute transport into healthy and powdery mildew-infected leaves of pea and uptake by powdery mildew mycelium. New Phytol 140:261–269. https://doi.org/10.1046/j.1469-8137.1998.00263.x
Dörmann P, Kim H, Ott T et al (2014) Cell-autonomous defense, re-organization and trafficking of membranes in plant-microbe interactions. New Phytol 204:815–822. https://doi.org/10.1111/nph.12978
Genre A, Bonfante P (2007) Check-in procedures for plant cell entry by biotrophic microbes: a survey of early plant-cell responses. Mol Plant-Microbe Interact 20:1023–1030. https://doi.org/10.1094/MPMI-20-9-1023
Genre A, Chabaud M, Timmers T et al (2005) Arbuscular mycorrhizal fungi elicit a novel intracellular apparatus in Medicago truncatula root epidermal cells before infection. Plant Cell 17:3489–3499. https://doi.org/10.1105/tpc.105.035410
Genre A, Ortu G, Bertoldo C et al (2009) Biotic and abiotic stimulation of root epidermal cells reveals common and specific responses to arbuscular mycorrhizal fungi. Plant Physiol 149:1424–1434. https://doi.org/10.1104/pp.108.132225
Griffis AHN, Groves NR, Zhou X, Meier I (2014) Nuclei in motion: movement and positioning of plant nuclei in development, signaling, symbiosis, and disease. Front Plant Sci 5:129. https://doi.org/10.3389/fpls.2014.00129
Gross P, Julius C, Hahlbrock K (1993) Translocation of cytoplasm and nucleus to fungal penetration sites is associated with depolymerization of microtubules and defence gene activation in infected, cultured parsley cells. EMBO J 12:1735–1744. https://doi.org/10.1002/j.1460-2075.1993.tb05821.x
Gupta M, Sharma G, Saxena D et al (2020) Dual RNA-Seq analysis of Medicago truncatula and the pea powdery mildew Erysiphe pisi uncovers distinct host transcriptional signatures during incompatible and compatible interactions and pathogen effector candidates. Genomics 112:2130–2145. https://doi.org/10.1016/j.ygeno.2019.12.007
Gupta A, Awasthi P, Sharma N et al (2022) Medicarpin confers powdery mildew resistance in Medicago truncatula and activates the salicylic acid signalling pathway. Mol Plant Pathol 00:1–18. https://doi.org/10.1111/mpp.13202
Heath MC, Nimchuk ZL, Xu H (1997) Plant nuclear migrations as indicators of critical interactions between resistant or susceptible cowpea epidermal cells and invasion hyphae of the cowpea rust fungus. New Phytol 135:689–700. https://doi.org/10.1046/j.1469-8137.1997.00710.x
Hoefle C, Huesmann C, Schultheiss H et al (2011) A barley ROP GTPase ACTIVATING PROTEIN associates with microtubules and regulates entry of the barley powdery mildew fungus into leaf epidermal cells. Plant Cell 23:2422–2439. https://doi.org/10.1105/tpc.110.082131
Inada N, Higaki T, Hasezawa S (2016a) Quantitative analyses on dynamic changes in the organization of host Arabidopsis thaliana actin microfilaments surrounding the infection organ of the powdery mildew fungus Golovinomyces orontii. J Plant Res 129:103–110. https://doi.org/10.1007/s10265-015-0769-9
Inada N, Higaki T, Hasezawa S (2016b) Nuclear function of subclass I actin-depolymerizing factor contributes to susceptibility in Arabidopsis to an adapted powdery mildew fungus. Plant Physiol 170:1420–1434. https://doi.org/10.1104/pp.15.01265
Kitaeva AB, Demchenko KN, Tikhonovich IA et al (2016) Comparative analysis of the tubulin cytoskeleton organization in nodules of Medicago truncatula and Pisum sativum: Bacterial release and bacteroid positioning correlate with characteristic microtubule rearrangements. New Phytol 210:168–183. https://doi.org/10.1111/nph.13792
Kobayashi I, Kobayashi Y, Yamaoka N, Kunoh H (1992) Recognition of a pathogen and a nonpathogen by barley coleoptile cells. III. Responses of microtubules and actin filaments in barley coleoptile cells to penetration attempts. Can J Bot 70:1815–1823. https://doi.org/10.1139/b92-225
Kobayashi Y, Kobayashi I, Funaki Y et al (1997a) Dynamic reorganization of microfilaments and microtubules is necessary for the expression of non-host resistance in barley coleoptile cells. Plant J 11:525–537. https://doi.org/10.1046/j.1365-313X.1997.11030525.x
Kobayashi Y, Yamada M, Kobayashi I, Kunoh H (1997b) Actin microfilaments are required for the expression of nonhost resistance in higher plants. Plant Cell Physiol 38:725–733. https://doi.org/10.1093/oxfordjournals.pcp.a029226
Koh S, André A, Edwards H et al (2005) Arabidopsis thaliana subcellular responses to compatible Erysiphe cichoracearum infections. Plant J 44:516–529. https://doi.org/10.1111/j.1365-313X.2005.02545.x
Leontovyčová H, Kalachova T, Trdá L et al (2019) Actin depolymerization is able to increase plant resistance against pathogens via activation of salicylic acid signalling pathway. Sci Rep 9:10397. https://doi.org/10.1038/s41598-019-46465-5
Meyer S, Heath M (1988) A comparison of the death induced by fungal invasion or toxic chemicals in cowpea epidermal cells. II. Responses induced by Erysiphe cichoracearum. Can J Bot 66:624–634. https://doi.org/10.1139/b88-088
Miklis M, Consonni C, Bhat RA et al (2007) Barley MLO modulates actin-dependent and actin-independent antifungal defense pathways at the cell periphery. Plant Physiol 144:1132–1143. https://doi.org/10.1104/pp.107.098897
Moral J, Montilla-Bascón G, Canales FJ et al (2017) Cytoskeleton reorganization/disorganization is a key feature of induced inaccessibility for defence to successive pathogen attacks. Mol Plant Pathol 18:662–671. https://doi.org/10.1111/mpp.12424
Newman-Griffis AH, del Cerro P, Charpentier M, Meier I (2019) Medicago LINC complexes function in nuclear morphology, nuclear movement, and root nodule symbiosis. Plant Physiol 179:491–506. https://doi.org/10.1104/pp.18.01111
Opalski KS, Schultheiss H, Kogel KH, Hückelhoven R (2005) The receptor-like MLO protein and the RAC/ROP family G-protein RACB modulate actin reorganization in barley attacked by the biotrophic powdery mildew fungus Blumeria graminis f.sp. hordei. Plant J 41:291–303. https://doi.org/10.1111/j.1365-313X.2004.02292.x
Qin L, Liu L, Tu J et al (2021) The ARP2/3 complex, acting cooperatively with class I formins, modulates penetration resistance in Arabidopsis against powdery mildew invasion. Plant Cell 33:3151–3175. https://doi.org/10.1093/plcell/koab170
Qu LH, Sun MX (2007) The plant cell nucleus is constantly alert and highly sensitive to repetitive local mechanical stimulations. Plant Cell Rep 26:1187–1193. https://doi.org/10.1007/s00299-007-0343-6
Scheler B, Schnepf V, Galgenmüller C et al (2016) Barley disease susceptibility factor RACB acts in epidermal cell polarity and positioning of the nucleus. J Exp Bot 67:3263–3275. https://doi.org/10.1093/jxb/erw141
Schmelzer E (2002) Cell polarization, a crucial process in fungal defence. Trends Plant Sci 7:411–415. https://doi.org/10.1016/S1360-1385(02)02307-5
Sharma G, Aminedi R, Saxena D et al (2019) Effector mining from the Erysiphe pisi haustorial transcriptome identifies novel candidates involved in pea powdery mildew pathogenesis. Mol Plant Pathol 20:1506–1522. https://doi.org/10.1111/mpp.12862
Skalamera D, Heath M (1998) Changes in the cytoskeleton accompanying infection-induced nuclear movements and the hypersensitive response in plant cells invaded by rust fungi. Plant J 16:191–200. https://doi.org/10.1046/j.1365-313x.1998.00285.x
Takemoto D, Hardham AR (2004) The cytoskeleton as a regulator and target of biotic interactions in plants. Plant Physiol 136:3864–3876. https://doi.org/10.1104/pp.104.052159
Timonen S, Drew E, Smith SE (2006) Effect of cytoskeletal inhibitors on mycorrhizal colonisation of tomato roots. Symbiosis 41:81–86
Yalovsky S, Bloch D, Sorek N, Kost B (2008) Regulation of membrane trafficking, cytoskeleton dynamics, and cell polarity by ROP/RAC GTPases. Plant Physiol 147:1527–1543. https://doi.org/10.1104/pp.108.122150
Yang L, Qin L, Liu G et al (2014) Myosins XI modulate host cellular responses and penetration resistance to fungal pathogens. Proc Natl Acad Sci U S A 111:13996–14001. https://doi.org/10.1073/pnas.1405292111
Zhou X, Graumann K, Meier I (2015) The plant nuclear envelope as a multifunctional platform LINCed by SUN and KASH. J Exp Bot 66:1649–1659. https://doi.org/10.1093/jxb/erv082
Acknowledgements
This work was supported by intramural funds from the Regional Centre for Biotechnology, Faridabad to DC., and a student fellowship from the Department of Biotechnology, Government of India to AS. We thank Dr. D. K. Banyal for the E. pisi isolate and Suraj Tiwari for technical assistance with the microscopy experiments.
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Supplementary file1
Effect of actin (Fig. S1) and microtubule (Fig. S2) depolymerization on E. pisi growth (DOCX 3432 KB)
Supplementary file2 3D rendering showing host nucleus position from fungal appressorium at 6 hpi (Movie S1) (AVI 762 KB)
Supplementary file3 3D rendering showing host nucleus position from fungal appressorium at 9 hpi (Movie S2) (AVI 724 KB)
Supplementary file4 3D rendering showing host nucleus position from fungal appressorium at 12 hpi (Movie S3) (AVI 841 KB)
Supplementary file5 3D rendering showing host nucleus position from fungal appressorium at 24 hpi (Movie S4) (AVI 726 KB)
Supplementary file6 3D rendering showing host nucleus position from fungal appressorium at 72 hpi (Movie S5) (AVI 737 KB)
Supplementary file7 3D rendering showing host nucleus position from fungal appressorium at 120 hpi (Movie S6) (AVI 2370 KB)
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Sharma, A., Chandran, D. Host nuclear repositioning and actin polarization towards the site of penetration precedes fungal ingress during compatible pea-powdery mildew interactions. Planta 256, 45 (2022). https://doi.org/10.1007/s00425-022-03959-3
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DOI: https://doi.org/10.1007/s00425-022-03959-3