Connexins Discussion Leaders: Amanda, Jocelyn, and Rory

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Connexins(Discussion Leaders Amanda, Jocelyn,
and Rory)

• Targeted Ablation of Connexin26 in the Inner Ear
  Epithelial Gap Junction Network Causes Hearing
  Impairment and Cell Death
• Human Connexin26 (GJB2) Deafness Mutations
  Affect the Function of Gap Junction Channels at
  Different Levels of Protein Expression

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Background

• Gap Junctions and Connexons
• Connexin 26
• Endocochlear Potential

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Gap Junctions

• Gap junctions let adjacent cells communicate.
  Dissolved molecules and electric signals may pass
  from one cell to the other through the channels
  formed by two connexons extending from adjacent
  cells (Life 104)
• Plasma membrane channels (OMIM link 121011)

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Connexons

• Gap junctions are comprised of six subunit
  proteins (OMIM link 121011)
• These transmembrane proteins are known as
  connexons and form the specific channels through
  which the rapid transport of ions or small
  molecules occurs (http//www.crg.es/deafness/cx26
  .htm)

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Connexons (continued)
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Connexin26
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Connexin26 (Continued)
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Cochlea
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Endolymph
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Endocochlear Potential
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Site of Endocochlear Potential
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