Noggin And Rna Case Study
Quiz De Almeida et al. Calreticulin is a secreted BMP antagonist, expressed in Hensen's node during neural induction
1) Explain two lines of evidence that Noggin, Chordin, and Follistatin are not the only neural inducing factors during development.
Targeted mouse deletion in Noggin, Chordin, or Follistatin genes on their own has only minor effects on neural development. Elimination of Noggin and Chordin produces a headless phenotype but neural tissue still forms, meaning deletion of these genes does not completely eliminate neural induction (Bachiller et al, 2000).
2) Why was Hensen’s Node used as the RNA source?
Hensen’s node is the neural organizer in amniotes which signals the primitive streak, the site of invagination during blastulation. Grafting of Hensen’s node to the anterolateral region generates a patterned nervous system (Stern, 2005). RNA from Hensen’s node was used because Hensen’s node is the site of neural induction and as such, proteins encoded by expressed transcripts in this region should be implicated in induction and gastrulation. RNA was used to generate a cDNA library selecting for secreted …show more content…
Movement of Hensen’s node to the proximal opaca in chick embryos induces neural markers in 12 hours (Dias and Schoenwolf, 1990). To identify Calreticulin induced epiblast competence, electroporation in the proximal opaca served as the research method. Calreticulin was electroplated to the area opaque and no induction of neural marker Sox2 occurred even in the presence of FGF, a promoter of BMP antagonism and neural induction, and/or BMP inhibitors. Sox2, a neural marker served as indication of sufficient of insufficient neural induction via electroporation.
5) What occurs in the nervous system of a Calreticulin mouse knockout and what does this tell you about it’s role in neural
1) Explain two lines of evidence that Noggin, Chordin, and Follistatin are not the only neural inducing factors during development.
Targeted mouse deletion in Noggin, Chordin, or Follistatin genes on their own has only minor effects on neural development. Elimination of Noggin and Chordin produces a headless phenotype but neural tissue still forms, meaning deletion of these genes does not completely eliminate neural induction (Bachiller et al, 2000).
2) Why was Hensen’s Node used as the RNA source?
Hensen’s node is the neural organizer in amniotes which signals the primitive streak, the site of invagination during blastulation. Grafting of Hensen’s node to the anterolateral region generates a patterned nervous system (Stern, 2005). RNA from Hensen’s node was used because Hensen’s node is the site of neural induction and as such, proteins encoded by expressed transcripts in this region should be implicated in induction and gastrulation. RNA was used to generate a cDNA library selecting for secreted …show more content…
Movement of Hensen’s node to the proximal opaca in chick embryos induces neural markers in 12 hours (Dias and Schoenwolf, 1990). To identify Calreticulin induced epiblast competence, electroporation in the proximal opaca served as the research method. Calreticulin was electroplated to the area opaque and no induction of neural marker Sox2 occurred even in the presence of FGF, a promoter of BMP antagonism and neural induction, and/or BMP inhibitors. Sox2, a neural marker served as indication of sufficient of insufficient neural induction via electroporation.
5) What occurs in the nervous system of a Calreticulin mouse knockout and what does this tell you about it’s role in neural