Summary
Coordinated orientation of cells within the tissue plane, important for convergent extension.
In depth
Core PCP proteins (Frizzled, Vangl, Flamingo) polarise cells across the epithelial plane, aligning hairs on the fly wing and cilia. Convergent extension narrows and lengthens the body axis by cell intercalation.
PCP coordinates cell orientation within tissues, important for hair and cilia alignment and neural tube closure. Core pathway components localise asymmetrically on cell edges.
Example: PCP mutations in mice cause open neural tubes.
Planar cell polarity (PCP) is the coordinated orientation of cells within the plane of a tissue, perpendicular to its apical-basal axis. It makes all the hairs on a fly wing point distally and all the stereocilia in the inner ear point the same way.
A set of core proteins (Frizzled, Van Gogh/Vangl, Flamingo, Prickle, Dishevelled) form asymmetric complexes at opposite sides of cell junctions, and the non-canonical Wnt pathway helps drive it. PCP drives convergent extension, where cells intercalate to narrow and lengthen a tissue, and is needed for neural tube closure.
Example: PCP defects cause neural tube defects and hearing loss in mouse mutants.
Frequently asked questions
What is Planar Cell Polarity?
Coordinated orientation of cells within the tissue plane, important for convergent extension.
Which area of biology covers Planar Cell Polarity, and how advanced is it?
Planar Cell Polarity is one of the 54 topics in Developmental Biology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Hedgehog Signalling, Wnt Signalling, Organogenesis.
Why does Planar Cell Polarity matter?
It organises tissue geometry.
Can you give an example of Planar Cell Polarity?
Neural tube defects occur with PCP gene mutations.
What should I learn before Planar Cell Polarity?
Work through the Beginner topics in Developmental Biology first, such as Fertilisation, Zygote, Embryo, then return to Planar Cell Polarity. Advanced topics assume the Intermediate vocabulary.
What topics are related to Planar Cell Polarity?
The closest topics to Planar Cell Polarity are Hedgehog Signalling, Wnt Signalling, Organogenesis, Spemann Organiser. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Planar Cell Polarity?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Planar Cell Polarity. To practise the whole of Developmental Biology, use the Developmental Biology quiz.
How is Planar Cell Polarity different from Hedgehog Signalling?
Planar Cell Polarity: Coordinated orientation of cells within the tissue plane, important for convergent extension. Hedgehog Signalling: A morphogen pathway patterning the neural tube and limbs through Gli transcription factors. Read both side by side and note what each one explains.
How should I study Planar Cell Polarity step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Hedgehog Signalling and explain the difference aloud. Finally, take the Developmental Biology quiz and come back to this page for any question you miss.