IMPDH1, short for inosine monophosphate dehydrogenase 1, is a key regulatory enzyme in the de novo synthesis of the purine base guanine [1]. It is involved in GTP biosynthesis, with its activity crucial for normal cellular function and metabolism. IMPDH1 can dynamically assemble filaments, and its regulation impacts metabolic processes [3].

Mutations in IMPDH1 are causative for RP10 autosomal dominant retinitis pigmentosa. IMPDH1-associated retinopathy often presents in the first decade of life with early macular involvement [1]. In cancer research, IMPDH1 is highly upregulated in colorectal cancer and promotes its growth in vitro and in vivo. The c-Myc-IMPDH1/2 axis promotes tumorigenesis by regulating GTP metabolic reprogramming, suggesting IMPDH1 inhibition as a cancer treatment option [2]. Also, in clear cell renal cell carcinoma, IMPDH1 is positively correlated with the metastasis-related gene YB-1, and they form an autoregulatory positive feedback loop related to tumor metastasis [4]. In gliomas, the ratio of IMPDH1 to IMPDH2 expression levels serves as a molecular indicator for treatment prognosis, with IMPDH1 playing a role in maintaining cellular GTP/GDP levels after DNA damage [5].

In conclusion, IMPDH1 is essential for purine nucleotide biosynthesis and has significant implications in retinal diseases and cancer. Research on IMPDH1, including through various genetic models (although not specifically KO/CKO mouse models in these references), helps in understanding disease mechanisms and developing potential therapeutic strategies for retinal disorders and cancer.