DLK1 and keratoconus: Being an upstream regulator of DLK1/CIDEA/LDLR/ACLY, the downregulation of SREBF1 in L-RFI KC steers can be directly linked to the upregulation of DLK1 and the downregulation of CIDEA/LDLR/ACLY, which further contribute to the lowered 18:2n-6, n-6, PUFA, and PUFA/SFA observed for the L-RFI KC steers (Fig. 4).