Cell fate

GUal precursors in the ventricular and subventricular zones can also express opioid receptors (Zhu et al. 1998 Reznikov et al. 1999 Stiene-Martin et al. 2001 Kim et al. 2006 Tripathi et al. 2008). Immature glia and adult progenitors express opioid receptors, which affect ceUular maturation (Stiene-Martin and Hauser 1990, 1991 Stiene-Martin et al. 1991 Persson et al. 2003,2006) and cell fate decisions (Kim et al. 2006). Importantly, gUal precursors (Khurdayan et al. 2004 Lawrence et al. 2004 Buch et al. 2007), and espedaUy immature oUgodendroglia (Khurdayan et al. 2004 Hauser et al. 2008), also appear to be vulnerable to opioids and HIV-1 proteins. 

Ziegler, L, The pteridine pathway in zebrafish regulation and specification during the determination of neural crest cell-fate, Pigment. Cell Res., 16, 172, 2003. 

In both worm and fly, the Ras protein acts as a switch that determine cell fate. In C. elegans, the activation of Ras determines the formation of vulval as opposed to hypodermal (skin) cells (for sequence of events, see Table 8.4). In Drosophila photoreceptors, the activation of Ras determines the development of R7 as a neuronal as opposed to a cone cell. In both cases, Ras proteins operate downstream of receptor tyrosine kinases that are activated by cell-cell interactions. 

Schmidt That s a harder question. The data are clear the mouse can make a duct, but it cannot put a lobuloalveolar structure on the outside of this. There is even a third question is Dl specifying some kind of a cell fate ... 

Asymmetric cell division is a universal mechanism utilized for the generation of cellular diversity during development (for reviews see Horvitz Herskowitz 1992, Guo Kemphues 1996, Shapiro Losick 1997, Jan Jan 1998). Asymmetric cell divisions during Drosophila embryonic development involve both extrinsic cues mediated through Notch and Delta and intrinsic cell fate determinants and play a major role in producing the distinct cell types which are... 

Miranda (Mir Shen et al 1997, Ikeshima-Kataoka et al 1997), Staufen (Li et al 1997, Broadus et al 1998, Schuldt et al 1998) and Partner of Numb (Pon Lu et al 1998), act as a link between the apically localized Insc and the basally localized cell fate determinants. These adaptors act downstream of insc and are also asymmetrically localised, similar to the cell fate determinants they help to localize, in an /Arc-dependent manner. 

FIG. 1. Localization of key proteins involved in the neuroblast asymmetric cell division. During late interphase a complex of proteins including Insc, Baz (and Pins) are localized to the apical cell cortex. This complex acts to mediate the basal cortical localization of the cell fate determinants Numb (and its partner Pon), Pros (and its partner Miranda) and pros RNA (and its partner Staufen) during mitosis. During interphase, Numb is cytoplasmic and Pros is localized to the apical cortex. 

Downstream events protein localization spindle orientation cell fate resolution... 

Broadus J, Fuerstenberg S, Doe CQ 1998 Staufen-dependent localisation of prospero mRNA contributes to neuroblast daughter-cell fate. Nature 319 792-795... 

Buescher M, Yeo SL, Udolph G et al 1998 Binary sibling neuronal cell fate decisions in the Drosophila embryonic central nervous system are non-stochastic and require inscuteable-mediated asymmetry of ganglion mother cells. Genes Dev 12 1858-1870... 

Skeath JB, Doe CQ 1998 Sanpodo and Notch act in opposition to Numb to distinguish sibling neuron fate in the Drosophila CNS. Development 125 1857-1865 Spana E, Doe CQ 1995 The prospero transcription factor is asymmetrically localised to the cell cortex during neuroblast mitosis in Drosophila. Development 121 3187-3195 Spana E, Doe CQ 1996 Numb antagonises Notch signaling to specify sibling neuron cell fate. Neuron 17 21—26... 

Tio M, Zavortink M, Yang X, Chia W 1999 A functional analyses of inscuteable and its roles during Drosophila asymmetric cell divisions. J Cell Sci 112 1541—1551 Uemura T, Shepherd S, Ackerman L, Jan LY, Jan YN 1989 numb, a gene required in determination of cell fate during sensory organ formation in Drosophila embryos. Cell 58 349-360... 

Chia No, what determines fate in the daughter cells is whether or not they inherit the cell fate determinants which are normally localized as basal crescents. If the crescents of cell fate determinants are not fixed, they will not always overlie one of the spindle poles. Consequently, their segregation to the daughter cells will not always be asymmetric. 

Chia Not necessarily. For a certain proportion of the time, the distribution is throughout the cortex. The cell fate determinants were totally randomly distributed throughout the cortex, with no crescent formation. However, at other times we still get crescents, which are mislocalized. 

Nurse If instead of a whole dozen fates you have, let s say, just five, you end up with an imaginal disc that is smaller over all, compared with the one with all dozen. This suggests that determining the overall proper organ size requires a proper mixture of cells with all the cell fates, rather than a limited set. Would this be consistent ... 

The temporal control of cell cycle and cell fate in Caenorhabditis elegans... 

Cell cycle-dependent cell fate choices... 

In many developing systems, decisions about cell fate are influenced by cell cycle status (McConnell Kaznowski 1991, Weigmann Lehner 1995, Lehner Lane... 

---