Article
Author: Chamakuri, Srinivas ; Kent, Katarzyna ; Sutton, Courtney M ; Sankaran, Banumathi ; Wilkinson, Jennifer ; Li, Jian-Yuan ; Jimmidi, Ravikumar ; Bohren, Kurt M ; Young, Damian W ; Vasquez, Yasmin M ; Palaniappan, Murugesan ; Li, Feng ; Tan, Zhi ; Palmer, Stephen S ; Ma, Lang ; Wang, Yong ; Robers, Matthew B ; Yu, Zhifeng ; Matzuk, Martin M ; Ku, Angela F ; Ye, Qiuji ; Wang, Jian ; Sharma, Kiran L ; Hakenjos, John M ; Chen, Ruihong ; Qin, Xuan ; Teng, Mingxing ; Kim, Choel ; Ta, Hai Minh ; Madasu, Chandrashekhar
Men or mice with homozygous serine/threonine kinase 33 (
STK33
) mutations are sterile owing to defective sperm morphology and motility. To chemically evaluate STK33 for male contraception with STK33-specific inhibitors, we screened our multibillion-compound collection of DNA-encoded chemical libraries, uncovered potent STK33-specific inhibitors, determined the STK33 kinase domain structure bound with a truncated hit CDD-2211, and generated an optimized hit CDD-2807 that demonstrates nanomolar cellular potency (half-maximal inhibitory concentration = 9.2 nanomolar) and favorable metabolic stability. In mice, CDD-2807 exhibited no toxicity, efficiently crossed the blood-testis barrier, did not accumulate in brain, and induced a reversible contraceptive effect that phenocopied genetic
STK33
perturbations without altering testis size. Thus, STK33 is a chemically validated, nonhormonal contraceptive target, and CDD-2807 is an effective tool compound.