Journal: Nature Cardiovascular Research

Article Title: Oxidative phosphorylation is required for cardiomyocyte re-differentiation and long-term fish heart regeneration

doi: 10.1038/s44161-025-00718-x

Figure Lengend Snippet: a , Representative images of immunofluorescence staining showing Mef2 + PCNA + double-positive proliferating cardiomyocytes in TU and WIK at 7 dpci. Framed areas highlight the wound border zone (red) (scale bar, 300 μm). b , Quantification of Mef2 + PCNA + double-positive cells showing differences in proliferating cardiomyocytes in the border zone at 7 dpci but not at 21 dpci. c , Positive correlation of percentage of proliferating cardiomyocytes in the border zone between 7 dpci and 21 dpci. d , No correlation between 7 dpci border zone proliferation and 90 dpci wound length. e , Venn diagram displaying complete lack of overlap between genes correlating to 7 dpci border zone proliferation and 90-dpci wound length. f , g , No correlation between border zone proliferation and OXPHOS ( f ) or Glycolysis ( g ) at 7 dpci. h , Quantification of Mef2 + PCNA + cells showing no difference in proliferating cardiomyocytes in the border zone of 7 dpci KCL adult treated with inhibitor PF-04859989 or rotenone compared to DMSO control. i , Temporal wound length reduction of all strains between 1, 7, 21 and 90 dpci. Arrow highlighting the strong decrease in wound length in WIK between 7 dcpi and 21 dpci. j , Percentage of hearts completely regenerated at 90 dpci or with closed compact wall but remaining internal scar or with open compact wall and internal scar remaining. b , 7 dpci: AB, NA, TU n = 7; SAT, WIK n = 6; TL n = 5; KCL n = 3, 21 dpci: AB, SAT, TL, TU n = 5; NA n = 6; WIK n = 7; KCL n = 8 (biological replicates); h , PF-04859989, DMSO n = 6, rotenone n = 5 (biological replicates); i , AB: 1, 90 dpci n = 7; 7 dpci n = 8; 21 dpci n = 6. NA: 1, 7, 90 dpci n = 7; 21 dpci n = 11. SAT: 1, 7, 21, 90 dpci n = 7. TL: 1, 7, 90 dpci n = 7; 21 dpci n = 9. TU: 1, 7 dpci n = 7; 21 dpci n = 5; 90 dpci n = 6. WIK: 1, 7, 21, 90 dpci n = 7. KCL: 1, 7, 21, 90 dpci n = 8 (biological replicates); j , AB, NA, SAT, TL, WIK n = 7; TU n = 6; KCL n = 8. b , h , One-way ANOVA with Tukey’s test. c , d , f , g , Simple linear regression. h , Two-way ANOVA with Tukey’s test. i , Data presented as mean ± s.e.m. Mef2, myocyte enhancer factor 2; PCNA, proliferating cell nuclear antigen.

Article Snippet: Primary antibodies Mef2c (Biorbyt, orb256682), PCNA (clone PC10; Dako, M0879), GFP (Abcam, ab13970), MF20 (Developmental Studies Hybridoma Bank (DSHB), AB_2147781) and embcmhc N2.261 (DSHB, AB_531790) and secondary antibodies Alexa Fluor 488 (Invitrogen, anti-mouse A11001, anti-chick A11039 and anti-rabbit A21206) and Alexa Fluor 555 (Invitrogen, A31570 ) were prepared using TNB buffer at a ratio of 1:200.

Techniques: Immunofluorescence, Staining, Control

Journal: bioRxiv

Article Title: A balanced circadian glycolytic rhythm drives cardiomyocyte cell cycle progression during fish heart regeneration

doi: 10.1101/2025.09.15.675600

Figure Lengend Snippet: a , Frequency histogram of DNA intensity of cardiomyocyte nuclei at 14 dpci in Pachón and surface hearts. Images of dissociated cardiomyocytes DNA content, showing G1/2n, S, and G2M/4n nuclei, stained with MF20 and DAPI. b , S:G2M ratio comparison of Mef2c+/PCNA+ BZ CM between Pachón and surface at 10 dpci (unpaired two-tailed Student’s t-test). c , RNAscope analysis of slc2a1a in 7 dpci Pachón and surface heart sections, co-stained with MF20. d , e , Glycolysis (ECAR) and ATP levels comparison before injury and at 7 dpci between Pachón and surface (one-way ANOVA with Tukey). f , S:G2M ratio comparison of Mef2c+/PCNA+ BZ CM between surface treated with 2-Deoxy-d-glucose and control hearts at 10 dpci (unpaired two-tailed Student’s t-test). g - i , Rhythmic expression of genes representing the glycolytic process , slc2a1a and per1a in Pachón and surface hearts at 7 dpci. ( g to i ) dryR analysis. Scale bars 100 μm. BZ, border zone cardiomyocytes; W, wound.

Article Snippet: Primary antibodies, Mef2c (Biorbyt Cat# orb1336562), MF20 (DSHB), PCNA (Clone PC10, Dako), BrdU (Abcam Cat# ab6326), and secondary antibodies, Alexa Fluor® 488 and Alexa Fluor® 568 (Invitrogen), were prepared in TNB buffer at a ratio of 1:200.

Techniques: Staining, Comparison, Two Tailed Test, RNAscope, Control, Expressing

Journal: bioRxiv

Article Title: A balanced circadian glycolytic rhythm drives cardiomyocyte cell cycle progression during fish heart regeneration

doi: 10.1101/2025.09.15.675600

Figure Lengend Snippet: a , RNAseq experimental design schematic. Horizontal bars indicate light (14h) and dark (10h) periods, before and during sampling of 7 dpci WT and insra mutant hearts. b , Dot plot showing phase and amplitude of core clock genes in WT vs. insra hearts at 7 dpci. c , Rhythmic expression of per1b in WT and insra hearts at 7 dpci. d , Heatmap of genes identified as rhythmic exclusively in WT 7 dcpi hearts (biological replicates ≥ 3 sampled at 4-hour intervals over 20 hours). e , f , Rhythmic expression of genes indicative of insulin signaling and glycolysis between WT and insra hearts at 7 dpci. g , Glycolysis (ECAR) in WT vs. insra hearts at 7 dpci (unpaired two-tailed Student’s t-test). h , Expression levels of SLC2A1 at ZT0 in WT and insra hearts at 7dpci (unpaired two-tailed Student’s t-test). i , Rhythmic expression of pcna in WT and insra hearts at 7 dpci. j , PCNA/Mef2-positive BZ CM quantification in WT vs. insra hearts at 7 dpci. k , AFOG staining showing collagen (blue) and fibrin (red) scars in WT vs. insra zebrafish hearts at 14 dpci with scar area quantification (unpaired two-tailed Student’s t-test). l , Circadian heatmap of g lycolysis and OXPHOS subset genes in WT and insra at 7 dpci heart. m , Immunofluorescence for γH2a.x in MF20+ BZ CMs at 7 dpci (unpaired two-tailed Student’s t-test). n , Rhythmic expression of genes representing cellular stress in WT and insra hearts at 7 dpci. o , Circadian heatmap of mitotic subset genes in WT and insra hearts at 7 dpci. p , q , Rhythmic expression of cdk1 and anln in WT and insra hearts at 7 dpci. r , S:G2M ratio comparison in Mef2c+/PCNA+ BZ CM between WT and insra hearts at 14 dpci (unpaired two-tailed Student’s t-test). ( b to f , i , l , n to q ) dryR analysis. Scale bars 100 µm. V, ventricle; W, wound.

Article Snippet: Primary antibodies, Mef2c (Biorbyt Cat# orb1336562), MF20 (DSHB), PCNA (Clone PC10, Dako), BrdU (Abcam Cat# ab6326), and secondary antibodies, Alexa Fluor® 488 and Alexa Fluor® 568 (Invitrogen), were prepared in TNB buffer at a ratio of 1:200.

Techniques: Sampling, Mutagenesis, Expressing, Two Tailed Test, Staining, Immunofluorescence, Comparison