IGF-1 expression in transgenic chloroplasts. ELISAs show IGF-1 expression as percentage of the total soluble protein. A) Transgenic lines grown in a 16 hours light and 8 hours dark photoperiod; T0 are mature plants and T1 is a younger plant. B) Transgenic lines grown in continuous light for 13 days; C) Protein quantification by ELISA in young (Y), mature (M), and old (O) transgenic leaves. Young leaves were among the top few leaves; mature leaves were fully grown, present in the middle of the plant; the bottom few scenescing leaves were identified as old. D) Protein quantification by ELISA in seedlings and potted plants grown for 5 days and 15 days. E) IGF-1 expression in IGF-1s T0 and T1 transgenic lines. F) IGF-1s present in the total and soluble fractions of T1 and T0 generations.