MARVELD2 and retinal degeneration: To document the retinal degeneration at larval stages within zebrafish, cct4-14 mutants were utilized that feature loss of TRiC function due to their lack of the Cct4 subunit.[7] Semi-thin cross sections of retinas from cct4-14 homozygotes were generated and stained with Toluidine Blue at six dpf [Figure 1A].