KLF6 and obesity due to melanocortin 4 receptor deficiency: Cardiac EC clusters showed obesity-induced expression of the Krüppel-like (KLF) transcription factor genes Klf2, Klf3, Klf4, Klf6 and Klf9 (Fig. 3e and Extended Data Fig. 5e), which play an important role in vascular inflammation and response to shear stress28.