MP2:

MP2 (Midline Precursor 2), despite its name, forms bilaterally as part of the medial column of S1 NBs in both Drosophila and grasshopper (Doe, 1992; Broadus et al., 1995; Broadus and Doe, 1995).

The MP2 lineage was initially described in grasshopper (Bate and Grunewald, 1981; Goodman et al., 1984) as producing two intersegmental interneurons: vMP2 which projects anteriorly in a medial fascicle of the connective, and dMP2 which projects posteriorly in a different medial fascicle.

The same lineage has been observed in Drosophila (Thomas et al., 1984; Spana et al., 1995; Bossing and Technau, 1994), and MP2 has been used to study how Numb, Notch, and Sanpodo establish distinct sibling neuron fates (Spana et al., 1995; Spana and Doe, 1996; Skeath and Doe, 1998). We generated 18 MP2 lineages, 6 at stage 15, 3 at stage 16 and 9 at stage 17; our results are in agreement with Bossing and Technau (1996), except that we find dMP2 and vMP2 to extend axons across the entire length of the CNS at stage 17, making the MP2 and NB 2-5 the only two precursors that generate intersegmental interneurons spanning the length of the CNS at embryonic stage 17.

References:

Bate, C. M., and Grunewald, E. B. (1981). Embryogenesis of an insect nervous system II: a second class of neuron precursor cells and the origin of the intersegmental connectives. J Embryol exp Morph 61: 317-30.

Bossing, T., and Technau, G. M. (1994). The fate of the CNS midline progenitors in Drosophila as revealed by a new method for single cell labeling. Development 120: 1895-1906.

Broadus, J., Skeath, J. B., Spana, E. P., Bossing, T., Technau, G. M., and Doe, C. Q. (1995). New neuroblast markers and the origin of the aCC/pCC neurons in the Drosophila central nervous system. Mech Dev 53: 393-402.

Broadus, J. and Doe, C.Q. (1995) A conserved pattern of early CNS precursors is established by different mechanisms in Drosophila and Schistocerca. Development, 121, 3989-3996.

Goodman, C. S., Bastiani, M., Doe, C. Q., du Lac, S., Helfand, S. L., Kuwada, J. Y., and Thomas, J. B. (1984). Cell recognition during neuronal development. Science 225: 1271-79.

Skeath, J.B. and Doe, C.Q. (1998) Sanpodo and Notch act in opposition to Numb to distinguish sibling neuron fates in the Drosophila CNS. Development 125, 1857-1865.

Spana, E. P., Kopczynski, C., Goodman, C.S., and Doe, C. Q. (1995). Asymmetric localization of numb autonomously determines sibling neuron identity in the Drosophila CNS. Development 121: 3489-94.

Spana, E.P. and Doe, C.Q. (1996) Numb antagonizes Notch signaling to specify sibling neuron cell fates. Neuron, 17, 21-26.

Thomas, J. B., Bastiani, M. J., Bate, M., and Goodman, C. S. (1984). From grasshopper to Drosophila: a common plan for neuronal development. Nature 310: 203-207.