Czech ambitions to claim an 11th title have been dampened with the loss of both Karolina Pliskova (injury) and Petra Kvitova, who is sick but hoping to recover in time for Sunday.
Strycova, the 33rd-ranked Czech number two, will hope to put the first point on the board when she faces 19-year-old Kenin, who is still in search of her maiden WTA singles title, on the hardcourt of Prague's O2 Arena at 1300 GMT on Saturday.
Siniakova has replaced seventh-ranked Kvitova as the Czech number one after the two-time Wimbledon champion pulled out of Saturday's singles with a bad cold. On Sunday, Siniakova is due to face Kenin and Strycova will then take on Riske.
The teams may change after day one and if Kvitova gets better, she is certain to appear on the court on Sunday.
The US and the Czechs are the most successful teams in Fed Cup history, with the hosts also being second best in terms of head-to-head, winning only two of their previous 12 meetings.
Led by Kvitova and Pliskova, the Czechs have won five of the last seven editions including all three finals they have played on Prague's hardcourt.