| Claim/Topic | Key takeaway | Quantitative/statistical details | Best supporting source (citation id) | Publication year | URL |
|---|---|---|---|---|---|
| Target-family assignment for BRADI_1g22147v3 / A0A0Q3KVX9 | The UniProt annotation is consistent with a plant pectate lyase-like protein in polysaccharide lyase family 1 (PL1/PLL): plant PLLs are typically identified by the conserved Pec_lyase_C domain, sometimes with additional N-terminal regions and secretion signals; this is the appropriate family context for annotating the Brachypodium protein. | Rice PLL annotation framework identified 12 PLL genes; all carried a Pec_lyase_C domain, and a subset also carried Pec_lyase_N. Comparative analysis included Brachypodium sequences, supporting use of this framework for grass ortholog annotation. (pqac-00000000, pqac-00000001) | pqac-00000000 | 2018 | https://doi.org/10.1007/s00438-018-1466-x |
| Core enzymatic function | Pectate lyase (EC 4.2.2.2) cleaves homogalacturonan/pectate in the cell wall by a lyase, not hydrolase, mechanism. This supports annotating BRADI_1g22147v3 primarily as a pectin-remodeling/degrading enzyme. | Endo-PL = EC 4.2.2.2; exo-PL = EC 4.2.2.9. Substrates are α-1,4-linked galacturonic acid-rich homogalacturonan chains. (pqac-00000003, pqac-00000004, pqac-00000006) | pqac-00000003 | 2020 | https://doi.org/10.1007/978-3-030-53421-9_3 |
| Reaction mechanism | Plant/microbial pectate lyases cleave by β-elimination, generating a 4,5-unsaturated product at the nonreducing end rather than hydrolytic products. | Mechanistic hallmark: formation of a C4–C5 unsaturated bond in the product; distinguishes lyases from polygalacturonase hydrolases. (pqac-00000002, pqac-00000005, pqac-00000006) | pqac-00000002 | 2025 | https://doi.org/10.1146/annurev-arplant-083023-034055 |
| Substrate specificity: pectate lyase vs pectin lyase | Pectate lyases preferentially attack non- or low-methylesterified homogalacturonan (pectate), whereas pectin lyases act mainly on highly methylesterified pectin. This is central to predicting BRADI_1g22147v3 substrate preference. | PLs: active on low-DM pectin/pectate, usually Ca2+-dependent, alkaline optimum around pH ~8.5. PNLs: active on high-DM pectin, Ca2+-independent, acidic-to-neutral optimum ~5.5–7.5. (pqac-00000002, pqac-00000003, pqac-00000006) | pqac-00000002 | 2025 | https://doi.org/10.1146/annurev-arplant-083023-034055 |
| Catalytic/structural features supporting lyase annotation | Pectate lyase active sites are associated with acidic residues and Ca2+ coordination; this is compatible with domain-based annotation of BRADI_1g22147v3 as a canonical pectate lyase rather than a pectin lyase. | Review evidence notes PL active sites enriched for charged residues and three Asp residues involved in catalysis/Ca2+ coordination; a 2024 PeL study found seven conserved Asp residues, and Asp→Ala mutations reduced activity and virulence-associated function. (pqac-00000002, pqac-00000014) | pqac-00000014 | 2024 | https://doi.org/10.1038/s41467-023-44356-y |
| Likely cellular localization | Pectate lyase activity relevant to plant development occurs in the extracellular cell wall/apoplast, especially around pectin-rich middle lamella/primary wall regions. BRADI_1g22147v3 is therefore most plausibly a secreted/apoplastic enzyme. | Rice PLL annotation pipelines explicitly assessed N-terminal signal peptides; pathogen and plant-related PeLs are detected in apoplastic fluid in functional studies. (pqac-00000001, pqac-00000004, pqac-00000011) | pqac-00000011 | 2024 | https://doi.org/10.1038/s41467-023-44356-y |
| Biological process context in plants | PLL/PL proteins contribute to cell wall remodeling linked to growth, tissue softening, vascular development, pollen function, and reproductive development; BRADI_1g22147v3 likely participates in a similar cell-wall remodeling process in Brachypodium. | Reported family sizes/roles: 26 PLLs in Arabidopsis, 46 in Brassica rapa, 86 in Gossypium hirsutum, 65 in octoploid strawberry, 12 in rice; many are expressed in vascular tissues, and others function in ripening, senescence, fiber elongation, and xylem modification. (pqac-00000013) | pqac-00000013 | 2025 | https://doi.org/10.1146/annurev-arplant-083023-034055 |
| Monocot-specific context | Monocots generally have fewer pectin-related cell wall proteins than dicots, but grasses still retain PLL family members; this fits a plausible but possibly more specialized pectin-remodeling role for BRADI_1g22147v3 in Brachypodium. | Review of monocot cell wall proteomics reported 1,159 CWPs across surveyed monocot datasets overall and emphasized relatively low representation of pectin-related CWPs in monocots; rice has 12 PLL genes. (pqac-00000007, pqac-00000013) | pqac-00000007 | 2019 | https://doi.org/10.3390/ijms20081975 |
| Brachypodium-specific evidence status | Direct literature on BRADI_1g22147v3 itself appears limited. However, Brachypodium PLL sequences were included in grass comparative analyses, so annotation must rely mainly on UniProt/domain evidence plus family-level inference rather than gene-specific experiments. | No gene-specific expression/localization/phenotype for BRADI_1g22147v3 was extracted from the gathered literature; available comparative work confirms Brachypodium PLLs were part of phylogenetic datasets. (pqac-00000001) | pqac-00000001 | 2018 | https://doi.org/10.1007/s00438-018-1466-x |
| Recent family-level evidence for developmental functions | Recent plant studies reinforce that PL genes often show strong tissue specificity and measurable developmental phenotypes, supporting cautious functional inference for uncharacterized homologs like BRADI_1g22147v3. | In Fragaria vesca, 16 PL genes were identified; RNAi of FvePL1/4/7 increased fruit firmness by ~38%, total pectin by 41.14%, and water-soluble pectin by 65.42%; reproductive PLs showed strong co-expression networks (up to 727 correlated genes). (pqac-00000008, pqac-00000009, pqac-00000010) | pqac-00000010 | 2023 | https://doi.org/10.1186/s12864-023-09533-9 |


*Table: This table compiles the strongest available evidence supporting annotation of BRADI_1g22147v3/A0A0Q3KVX9 as a PL1-family pectate lyase, while clearly distinguishing direct Brachypodium evidence from broader plant family-level inference. It is useful for transparent functional annotation because it links each major claim to a specific citation, quantitative detail, and source URL.*