Oocyte-specific protein tyrosine kinase that phosphorylates and inhibits CDK1 and acts as a key regulator of meiosis. Required to maintain meiotic arrest in oocytes by phosphorylating CDK1 at 'Tyr-15', leading to inhibit CDK1 activity and prevent meiotic reentry (By similarity). ATP + L-tyrosyl-[protein] = ADP + H(+) + O-phospho-L-tyrosyl-[protein] Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. WEE1 subfamily.