CcFIG 2: Coelomocyte lineage
A. The right ventral and the left ventral coelomocyte pairs are derived from symmetrical divisions of MS granddaughters MSpp and MSap, respectively, during embryogenesis. Although the precursors for each pair are born during the burst of embryonic cell divisions, they delay their final divisions until most of the other embryonic cell divisions are completed.
B. The dorsal pair is derived from the post-embryonic M lineage at the late-L1 stage and they differentiate into coelomocytes during early L2.
C. Migration of the coelomocyte mother cells and M blast cell during embryogenesis between 250-400 minutes after first cleavage. The M cell is born on the left side, migrates posteriorly and toward the midline, and eventually migrates to the right side of the animal. The right and left coelomocyte mother cells are born next to the pharynx and then migrate posteriorly. All migrations are completed before the elongation of the embryo.
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