| Claim/Function | Evidence type (genetic/biochemical/cell biology/review) | Key experimental readout or statistic (include provided percentages N=... and key motif names) | System/organism | Key citation (author/year/journal + URL) | Notes for functional annotation |
|---|---|---|---|---|---|
| JOKA2 is the Solanaceae/potato homolog of plant NBR1 and functions as a selective autophagy cargo receptor | Biochemical, review | Potato Joka2 co-immunoprecipitates with ATG8CL; interaction requires an ATG8-interacting motif (AIM), because Joka2^AIM fails to bind; literature describes Joka2/NBR1 as a ubiquitin- and ATG8-binding selective autophagy receptor (pqac-00000000, pqac-00000005, pqac-00000014) | Solanum tuberosum-derived Joka2 studied in planta; broader Solanaceae/plant context | Dagdas et al. 2016, *eLife* — https://doi.org/10.7554/eLife.10856; Leong et al. 2022, *Essays Biochem.* — https://doi.org/10.1042/EBC20210063 | Supports annotation as a **selective autophagy receptor/adaptor**, not an enzyme or transporter; core biochemical role is bridging cargo to ATG8-positive autophagosomes |
| JOKA2 positively contributes to defense against *Phytophthora infestans* | Genetic, infection phenotyping | Overexpression of Joka2, but not Joka2^AIM, reduces late blight lesion size; silencing Joka2 increases lesion size, indicating a positive defense role dependent on AIM-mediated autophagy coupling (pqac-00000003, pqac-00000010) | *Nicotiana benthamiana* infection assays with *P. infestans* using potato/Solanaceae Joka2 constructs | Dagdas et al. 2016, *eLife* — https://doi.org/10.7554/eLife.10856 | Primary biological process: **antimicrobial selective autophagy / plant immunity** |
| JOKA2 preferentially functions with the potato ATG8CL autophagy branch | Biochemical, cell biology | Joka2 shows preferential association with ATG8CL rather than ATG8IL; overexpression increases GFP:ATG8CL-labeled autophagosomes and ATG8CL protein accumulation; AIM is required for productive interaction (pqac-00000000, pqac-00000003, pqac-00000004) | Potato/Solanaceae autophagy machinery in transient expression systems | Dagdas et al. 2016, *eLife* — https://doi.org/10.7554/eLife.10856 | Suggests cargo routing through a specialized **ATG8CL-associated selective autophagy pathway** |
| JOKA2-labeled autophagosomes are redirected to the pathogen interface (haustorial region/EHM) during infection | Cell biology | Full-length Joka2:BFP localizes to perihaustorial puncta/EHM in **92% (N=50)** of observations; Joka2:BFP-labeled perihaustorial autophagosomes reported in **100% (N=140)** of scored haustoria; Joka2 and ATG8CL associate with the extrahaustorial membrane marker REM1.3 (pqac-00000006, pqac-00000008, pqac-00000025) | *N. benthamiana* cells infected by *P. infestans*; potato/Solanaceae Joka2 | Dagdas et al. 2018, *eLife* — https://doi.org/10.7554/eLife.37476 | Subcellular localization for annotation: **cytoplasmic puncta/autophagosomes**, especially **perihaustorial autophagosomes at the extrahaustorial membrane** during oomycete infection |
| ATG8 binding contributes to perihaustorial recruitment, but is not sufficient by itself | Cell biology, mutational analysis | Joka2^AIM still forms perihaustorial puncta at reduced frequency **74% (N=42)**, but coincidence with ATG8CL puncta is rare **19% (N=37)**; thus AIM-dependent ATG8 binding is important, yet additional determinants are needed (pqac-00000001, pqac-00000006, pqac-00000008) | *P. infestans* haustoriated cells expressing Joka2 variants | Dagdas et al. 2018, *eLife* — https://doi.org/10.7554/eLife.37476 | Functional motif annotation: contains a critical **AIM/LIR-like motif** for ATG8 engagement, but full focal recruitment requires multi-domain architecture |
| PB1/ZZ-mediated oligomerization or partner interactions are critical for focal recruitment | Cell biology, domain truncation | Joka2Δ1-487, lacking PB1/ZZ but retaining ubiquitin-binding and ATG8-interacting motifs, fails to accumulate perihaustorially: **1% (N=72)** or **1.3% of haustoria**; authors conclude PB1/ZZ-mediated oligomerization/association is critical (pqac-00000006, pqac-00000007, pqac-00000009) | *N. benthamiana–P. infestans* pathosystem | Dagdas et al. 2018, *eLife* — https://doi.org/10.7554/eLife.37476 | Domain-based annotation: **PB1 domain** likely mediates self-assembly/oligomerization; **ZZ region** contributes to recruitment and/or partner binding |
| Domain architecture matches UniProt M1BJF6 and canonical plant NBR1/JOKA2 receptors | Domain analysis, review, figure-based evidence | Figure schematic lists **PB1 – ZZ – NBR1/FW – UBA – AIM – UBA**; reviews describe plant NBR1 proteins as PB1/ZZ/FW(NBR1)/AIM/UBA receptors, with ubiquitin binding mainly via C-terminal UBA and ATG8 binding via AIM/LIR (pqac-00000006, pqac-00000014, pqac-00000025) | Plant NBR1 family; Joka2-specific domain map from Solanaceae study | Dagdas et al. 2018, *eLife* — https://doi.org/10.7554/eLife.37476; Zhang & Chen 2020, *Cells* — https://doi.org/10.3390/cells9122562 | Strongly supports mapping to UniProt M1BJF6 domains: **PB1-like, Nbr1_FW, UBA**; molecular function is scaffold/receptor for selective autophagy |
| JOKA2 likely binds ubiquitinated cargo but can also participate in aggregate/condensate-like assemblies | Review, comparative mechanism | Reviews assign UBA-dependent ubiquitin binding and PB1-dependent oligomerization to plant NBR1/Joka2; Joka2 forms multimeric aggregates, and plant NBR1 can concentrate cargos in condensates/aggrephagy-like structures (pqac-00000012, pqac-00000014, pqac-00000024) | Plant NBR1/Joka2 family | Leong et al. 2022, *Essays Biochem.* — https://doi.org/10.1042/EBC20210063; Zhang & Chen 2020, *Cells* — https://doi.org/10.3390/cells9122562 | Functional inference for potato JOKA2: **cargo receptor for ubiquitinated and possibly non-ubiquitinated aggregated substrates** |
| Pathogen effector PexRD54 antagonizes JOKA2 by competing for ATG8CL | Biochemical, cell biology, pathogenesis | *P. infestans* RXLR effector PexRD54 carries its own AIM, binds ATG8CL, stimulates ATG8CL autophagosome formation, and competitively depletes Joka2 from ATG8CL complexes/autophagosomes in a dose-dependent manner (pqac-00000000, pqac-00000002, pqac-00000004, pqac-00000016) | Potato late blight pathosystem / Solanaceae infection models | Dagdas et al. 2016, *eLife* — https://doi.org/10.7554/eLife.10856; King et al. 2024, *MPMI* — https://doi.org/10.1094/MPMI-09-23-0122-FI | Places JOKA2 in a defined pathway: **host selective autophagy targeted by oomycete virulence effectors** |
| Current 2024 understanding extends plant NBR1 biology to LLPS and non-ubiquitinated cargo recognition, informing JOKA2 functional inference | Recent primary research, review | Arabidopsis NBR1 uses **ZZ + FW** for non-ubiquitinated cargo recognition and undergoes LLPS before ATG8-mediated sequestration; PB1 is required for puncta, UBA contributes to puncta, and LIR mutant **WDPI661-664AAAA** blocks ATG8 recruitment (pqac-00000018, pqac-00000019, pqac-00000020, pqac-00000021) | Arabidopsis; inference to conserved plant NBR1/Joka2 receptors | Yan et al. 2024, *Autophagy* — https://doi.org/10.1080/15548627.2024.2391725 | Not potato-specific, but strengthens annotation that JOKA2 may combine **cargo recognition + condensate formation + ATG8 delivery** |
| Translational relevance: NBR1-mediated selective autophagy is an actionable crop-resilience pathway | Review, application-oriented synthesis | 2024 reviews highlight NBR1 overexpression improving salt tolerance in poplar, NBR1 importance in drought/salt responses, and the broader possibility of engineering ATG/receptor pathways for stress resilience and disease resistance (pqac-00000028, pqac-00000030) | Crop and model plant systems | Petersen et al. 2024, *Autophagy Reports* — https://doi.org/10.1080/27694127.2024.2395731 | For annotation context, JOKA2 belongs to a receptor class with **agronomic relevance** in immunity and abiotic stress adaptation |
| Expert consensus places JOKA2/NBR1 at the extrahaustorial membrane as a focal immune trafficking component | Review | 2024 expert review states NBR1/Joka2 is recruited to the EHM in ATG8CL-positive autophagosomes to restrict *P. infestans* growth, while PexRD54 prevents Joka2-mediated antimicrobial cargo delivery (pqac-00000016) | Oomycete–plant interface review | King et al. 2024, *MPMI* — https://doi.org/10.1094/MPMI-09-23-0122-FI | Useful concise annotation statement: **JOKA2 is a selective autophagy receptor operating at focal host–pathogen interfaces** |


*Table: This table summarizes the main experimental and review-based evidence supporting annotation of potato/Solanaceae JOKA2 as an NBR1-family selective autophagy receptor. It highlights domain architecture, localization, pathway role in late blight defense, and the strongest quantitative readouts available from the cited studies.*