lin-4S RNA was not detected in embryos, or early L1 larvae, and was first detected during the latter half of the L1 larval stage, 12 h after larval development began.
lin-4S levels continued to increase through the L1 and during subsequent stages of development (
lin-4S RNA is also present in high levels in adult worms).
lin-4L is expressed at very low levels and was difficult to detect by these Northern blots.