Journal: BMC Rheumatology

Article Title: Associations of PTPN22 and PADI4 polymorphisms with rheumatoid arthritis in ASWAN

doi: 10.1186/s41927-025-00566-z

Figure Lengend Snippet: Serum PTPN22 ROC curve

Article Snippet: We used a Sandwich ELISA kit from BT Lab to measure PTPN22 and PADI4 in serum samples from rheumatoid arthritis patients and healthy individuals.

Techniques:

Journal: Human Molecular Genetics

Article Title: A loss-of-function variant of PTPN22 is associated with reduced risk of systemic lupus erythematosus

doi: 10.1093/hmg/ddn363

Figure Lengend Snippet: Q263 allele defines the ancestral LYP variant. Alignment of catalytic domains of LYP from Homo sapiens (gi:48928054), Pan troglotides (gi:114558717), Macaca mulatta (gi:109014421), Mus musculus (gi:6679555), Rattus Norvegicus (gi:157824150), Bos taurus (gi:119889627) and Gallus gallus (gi:118102481). The residue in position 263 is highlighted in gray.

Article Snippet: Alignment of catalytic domains of LYP from Homo sapiens (gi:48928054), Pan troglotides (gi:114558717), Macaca mulatta (gi:109014421), Mus musculus (gi:6679555), Rattus Norvegicus (gi:157824150), Bos taurus (gi:119889627) and Gallus gallus (gi:118102481).

Techniques: Variant Assay, Residue

Journal: Human Molecular Genetics

Article Title: A loss-of-function variant of PTPN22 is associated with reduced risk of systemic lupus erythematosus

doi: 10.1093/hmg/ddn363

Figure Lengend Snippet: LYP–Q263 shows decreased phosphatase activity. (A) The Q263 allele shows lower phosphatase activity than R263. JTAg cells were transfected with HA–LYP–R263 or HA–LYP–Q263 or an inactive (C227S) variant of HA–LYP–R263. HA–LYP was immunoprecipitated from cell lysates and its phosphatase activity was assessed under Vmax conditions using DiFMUP as a substrate. Left panel shows anti-HA blot of an aliquot of immunoprecipitations (IPs) from cells transfected with HA–LYP–R263 (lane 1), HA–LYP–Q263 (lane 2) or HA–LYP–C227S (lane 3). Histogram showing average ± SD activity of immunoprecipitated HA–LYP–R263 (black column) or HA–LYP–Q263 (shaded column), normalized for LYP expression as assessed by anti-HA blots of fractions of IPs taken before resuspension in the final phosphatase buffer, and corrected for the activity associated with HA–LYP–C227S immunoprecipitates. The statistical significance of the difference between LYP–Q263 and LYP–R263 was calculated by Student’s t-test (P-value shown above the Q263 column). Figure shows one representative experiment of three independent replicates with similar results. (B) Coomassie-stained polyacrylamide gel showing 300 ng of Cat-R263 (lane 1) or Cat-Q263 (lane 2). (C–E) Activity of Cat-R263 (continuous graphs) and Cat-Q263 (dotted graphs) on three different substrates. Panels show activity on 14LckpY394, a 14 amino acid phospho-peptide ARLIEDNE(pY)TAREG, derived from the Tyr394 auto-phosphorylation site of Lck (C), or p-NPP (D), or DiFMUP (E). The average ± SD activity of Cat-R263 (filled squares) and Cat-Q263 (open squares) measured in triplicate was plotted versus substrate concentration, and data were fitted to the Michaelis–Menten equation (for p-NPP and DiFMUP) or the Michaelis–Menten with substrate inhibition (for the 14LckpY394 peptide) equations (continuous and dotted lines). Calculated catalytic parameters with 95% CI are reported below each graph.

Article Snippet: Alignment of catalytic domains of LYP from Homo sapiens (gi:48928054), Pan troglotides (gi:114558717), Macaca mulatta (gi:109014421), Mus musculus (gi:6679555), Rattus Norvegicus (gi:157824150), Bos taurus (gi:119889627) and Gallus gallus (gi:118102481).

Techniques: Activity Assay, Transfection, Variant Assay, Immunoprecipitation, Expressing, Staining, Derivative Assay, Phospho-proteomics, Concentration Assay, Inhibition