Fig. 6: RAC1 participates in the regulation of glucose metabolism in B cells.

A Top 15 enriched up-regulated and down-regulated KEGG pathways for DETs in Usp25 KO mice models (n = 3). Asterisks represent the pathways associated with the RAC1 transcripts. B Heatmap showing the expression change of transcripts involved in the down-regulated KEGG pathways in mouse models. C KEGG pathway enrichment analysis of DETs in patients and mouse models. Asterisks represent the pathways associated with the RAC1 gene (n = 5). D, E The mRNA levels (D) and protein (E) levels of HCs and IgG4-RD patients / Usp25 KO and WT were analyzed by RT-PCR and Western blot, respectively (n = 3). F WT B cell lysates immunoprecipitated with RAC1 and immunoblotted for USP25. G HCs and IgG4-RD patients B cell lysates immunoprecipitated with RAC1 and immunoblotted for Ubiquitin. H–J Purified B cells of IgG4-RD patients and HCs were stimulated in the same way as in (Fig. 2G) except stained for LAMP1 and RAC1 (scale bar = 2.5 μm) and shown are representative images captured using confocal (H). The B cells were analyzed for the MFI of RAC1 (I) and the correlation coefficient of LAMP1/ RAC1 (J). K–M Purified B cells from Usp25 KO and WT were stimulated with 10 μg/ml AF 594-F(ab′)₂ Ig (M  + G), fixed, permeabilized, and stained for ALDOA, F-actin, and nuclei using DAPI (scale bar =2.5 μm) and shown are representative images captured using confocal (K). B cells were analyzed for the MFI of F-actin (L) and the correlation coefficient between F-actin and ALDOA (M). All images were representative images from 3 independent experiments. Data points in (D, I, J, L, and M) are represented as Mean ± SED. Statistical significance was based on two-tailed unpaired Student’s t-test. Relevant p values are given in the graph. *P < 0.05; **P < 0.01; ***P < 0.001. Source data are provided as a Source Data file.