Extension step in the second cycle will produce a product that will be much shorter than the 'long product'; this is the 'correct' PCR product and represents the target sequence

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#Id: 166

#Unit 5. Developmental Biology

Foregut endoderm and cardiac mesoderm cause the synthesis of the Otx2 transcription factor in the head ectoderm during the late gastrula stage

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#Id: 167

#Unit 5. Developmental Biology

The anterior neural plate produce the next signals, that promotes the synthesis of the Pax6 transcription factor in the anterior ectoderm.

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#Id: 168

#Unit 5. Developmental Biology

Expression of Pax6 protein constitute the competence of the surface ectoderm to respond to the optic vesicle.

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#Id: 169

#Unit 5. Developmental Biology

The optic vesicle secrete two paracrine factors:

 BMP4

 FGF8

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#Id: 170

#Unit 5. Developmental Biology

BMP4 

A protein that is received by the lens cells and induces the production of the Sox transcription factors.

TLS Online TPP Program

#Id: 171

#Unit 5. Developmental Biology

FGF8 

A secreted signal that is received by the lens cells and induces the production of the L-Maf transcription factor.