18. TIGHT JUNCTIONS
ZONULA OCCLUDENS
• APICAL BAND
• SERIES OF FOCAL ADHESION
• OCClUDENS--- ZO---- ACTIN
• BARRIER luminal &intercellular space
• INTEGRITY OF DOMAINS
• IMPERMEABILITY number of fusions
• LIMITED RESISTANCE TO MECHANICAL
STRESS
19.
20. ANCHORING JUNCTIONS
ZONULA ADHERENCE
• BELOW OCCLUDENS
• BAND reinforcing ZONULA OCCLUDENS
• 20-30nm space
• TRANSMEMBRANE PROTEIN
CADHERIN- CATENIN-ACTIN (actinin,vinculin)
• MECHANICAL STABILITY
• FACIA ADHERENCE SHEET LIKE,
CELLS OTHER THAN EPITHELIA
21.
22. DESMOSOMES
• MACULA ADHERENCE
• STRONG ATTACHMENT
• SPOT JUNCTIONS
• INTERCELLULAR SPACE 30nm
• TRANS MEMBRANE PROTEIN
CADHERIN FAMILY (desmoglein & collin)
• ATTACHMENT PLAQUE (desmoplakin)
• INTERMEDIATE FILAMENT
23.
24. GAP JUNCTION
NEXUS
• COMMUNICATING JUNCTIONS
• VARIOUS TISSUES (coordinated)
– EPITHELIUM, SMOOTH & CARDIAC
MUSCLE, NERVOUS
• EXCHANGE(ions,regulatory mol.& small metabolite)
• TWO CONNEXONS
• Connexins 6 (dumbell)
• HYDROPHILIC PORE 2nm