Fig. 5b

Fig. 5b (c) Up-regulation in the presomitic mesoderm. nrarpa has oscillating bands of expression and a small region of adaxial expression in the presomitic mesoderm. ZFmu2B8s and ZFmu9s are up-regulated in the paraxial mesoderm as the new somites are formed. ZFmu2B8s is also expressed in the developing somites, whereas ZFmu9s has ventral staining in the sclerotome of the anterior somites. sox11b is expressed in the posterior somites in addition to strong neural staining. (d) Dorsal expression. This domain of expression is seen in known genes such as alcam and also 3 novel transcripts ZFmu3D7s, ZFmu13s and ZFmu110s. ZFmu3D7s is expressed in the anterior somites, whereas ZFmu13s and ZFmu110s are expressed in all somites. The expression patterns of ZFmu3D7s and ZFmu110s are very dynamic throughout development with ZFmu3D7s being expressed in a number of different tissues. e. Other domains of expression. The remaining 9 cDNAs were difficult to group. ZFmu1A10s, ZFmu1A1s, nat13 and pwp2h all have general staining in the adaxial and paraxial somite. ZFmu5B5s has a punctate expression that becomes restricted to the somite boundaries. twist1a has weak expression in the anterior row of cells in the somite, strong ventral expression in the sclerotome in the anterior somites and is also expressed in the floor plate. ZFmu5B2s is expressed strongly in the segmental plate and somites with the expression stronger around the horizontal myoseptum in the anterior somites. cx43.4 is expressed strongly in the segmental plate and towards the lateral edge of the myotome and ventrally in the sclerotome in the anterior somites. ZFmu3B11s is expressed only in the posterior half of the whole embryo, including all the somites and the lateral neural crest, while the head region has no staining. In the posterior region, there is weaker staining around the notochord.