Fig. 4: The JAK–STAT signalling pathway regulates Pepck1 and Pdk expression in the fat body.
From: Hepatic gluconeogenesis and PDK3 upregulation drive cancer cachexia in flies and mice
a,b, Quantitative reverse transcription PCR (qRT–PCR) of Pepck1 (a) and Pdk (b) mRNA in the fat body of fed, starved, and refed flies at day 6 (n = 3). c,d, Pepck1 (c) and Pdk (d) mRNA in the fat body of control, Yki flies, and Yki flies with fat-body InR-ca (constitutive-activated form of InR) expression at day 8 (n = 3). e,f, Pepck1 (e) and Pdk (f) mRNA in the fat body of flies with or without ISC Upd3 expression at day 8 (n = 3). g, Data from the ChIP–seq database indicating enrichment of Stat92e binding at the Pepck1 and Pdk gene regions. The transcript isoforms Pepck1-RA and Pdk-RD were used to indicate the gene regions. Inverted triangle, STAT-binding motif (2N, TTCNNGAA; 3N, TTCNNNGAA; 4N, TTCNNNNGAA). h, ChIP revealed the enrichment of haemagglutinin (HA)-tagged Stat92E binding at the Pepck1 and Pdk gene regions, shown by fold changes relative to control IgG at day 8 (n = 3 biological replicates). Neg, negative control. i, Images of gut tumours and phenotypes of Yki flies with or without fat-body hop or Stat92e depletion at day 6. j, Quantification of gut tumours (GFP signal, arbitrary units) of Yki flies with or without fat-body hop or Stat92e depletion at day 6 (n = 12). k, Total pH3 counts per gut of control flies and Yki flies with or without fat-body hop or Stat92e depletion at day 6 (n = 10). l, Quantification of bloating phenotypes (A/H ratio) of Yki flies with or without fat-body hop or Stat92e depletion at day 6 (n = 9). m, Body-fluid levels of Yki flies with or without fat-body hop or Stat92e depletion at day 6 (n = 4). n,o, Pepck1 (n) and Pdk (o) expression in the fat body of control, Yki flies, and Yki flies with fat-body hop depletion at day 6 (n = 3). p,q, Pepck1 (p) and Pdk (q) expression in the fat body of Yki flies and Yki flies with fat-body Stat92e depletion at day 6 (n = 3). r,s, Whole-body trehalose (r) and glucose (s) levels of control (n = 8), Yki flies (n = 8), and Yki flies with fat-body hop (n = 5) or Stat92e (n = 6) depletion at day 6. Statistical significance was assessed using the unpaired two-sided Student’s t-test (e,f,p,q) and ordinary one-way ANOVA (a–d,h,j–o,r,s). Error bars indicate the s.d., with the mean as the centre. See also Extended Data Fig. 4.
