Dissimilar regulation of cell differentiation in mesencephalic (cranial)and sacral (trunk) neural crest cells in vitro

Abstract

During development neural crest cells give rise to a wide variety of specialized cell types in response to cytokines from surrounding tissues. Depending on the cranial-caudal level of their origin, different populations of neural crest cells exhibit differential competence to respond to these signals as exemplified by the unique ability of cranial neural crest to form skeletal cell types. We show that in addition to differences in whether they respond to particular signals, cranial neural crest cells differ dramatically from the trunk neural crest cells in how they respond to specific extracellular signals, such that under identical conditions the same signal induces dissimilar cell fate decisions in the two populations in vitro. Conversely, the same differentiated cell types are induced by different signals in the two populations. These in vitro differences in neural crest response are consistent with in vivo manipulations. We also provide evidence that these differences in responsiveness are modulated, at least in part, by differential expression of Hox genes within the neural crest.

Expression of chondrogenic potential of mouse trunk neural crest cells by FGF2 treatment

“…2G). No cells expressing collagen type II were observed, even when using culture conditions used by Abzhanov et al (2003;0/5;Fig. 2H).…”

“…Because it has been shown that FGF2 treatment reduces the survival of chick trunk neural crest cells (Abzhanov et al, 2003), we examined the effect of FGF2 on the survival of mouse trunk neural crest cells using a similar method to that used by Abzhanov et al (2003). A colony (each colony was derived from a neural tube explant) was scored as dead if less than 5% of the cells of the colony at culture day 2 remained on the plate after 10 days in culture.…”

“…2E,F,I). It has been reported that chick trunk neural crest cells undergo chondrogenesis in long-term cultures (McGonnell and Graham, 2002;Abzhanov et al, 2003). Therefore, we cultured mouse trunk neural crest cells in the absence of FGF2 for 20 days.…”

“…3). This strategy revealed that chondrocytes express FGF receptor (FGFR) 1 ( Abzhanov et al (2003) have shown that overexpression of the posterior group of Hox genes (Hox9-Hox13 paralogous groups) blocks chondrogenesis of chick trunk neural crest cells in long-term cultures. Therefore, we examined the expression of Hox 9 in mouse trunk neural crest cells treated with FGFs and found that, although the percentage of anti-Hox9 -positive cells per total number of cells in a neural crest cell colony decreased under all conditions examined (Fig.…”

Induction and modulation of smooth muscle differentiation in Xenopus embryonic cells

“…Exogenous addition of recombinant BMP2 to cultured chicken neural crest cells highlights such effects as BMP2 appears to elicit the differentiation of several cell types, including smooth muscle cells (Abzhanov et al, 2003). Gene ablation studies in the mouse have identified BMP signals as regulator of the SMC differentiation from neural crest cells (Kaartinen et al, 2004).…”