micro anatomy mini 1b

epithelium, connective, muscle and nervous

basal lamina and reticular lamina

• -located b/t the basal side of the cell and the lamina densa
• -made mostly of glycoproteins(laminin and entactin) as well as transmembrane proteins(integrins and dystroglycans)

• -b/t lamina lucida and reticular lamina
• -Collagen 4, coated with proteoglycans(perlacean, which has lots of HepSO4, a GAG)
• -Coll 4= filter
• -HepSO4= negative charges restricts neg charged molecules

• -Collagen 3 (reticular fibers)
• -part of the basement membrane made by FIBROBLASTS, which make fibronectin

• -Collagen 7
• -attach basal lamina to the lamina retiularis
• made by FIBROBLAST

• -attach basal lamina to elastic fibers
• made by FIBROBLAST

• -part of the lamina lucida
• -has binding sites for Coll 4, HepSO4 and integrins (of epithelial cells and anchor PM of cell to the basal lamina

• absense of dystrophin leading to muscular weakness
• -dystrophin binds EC laminin and IC actin filaments
• - MALES ONLY (located on X chr)

• -mutation of Coll 7 gene
• -causes defective anchorig fibrils
• -presents as erosion in flexural creases, subepdermal blistering at lamina lucida level
• -in scarring types, blisters are beneath lamina densa

• trachea- ciliated PCE with goblet cells
• epididymis- PCE with stereocilia

• -long microvilli
• - increase absoption by increasing surface area

• -'immotile cilia syndrome'
• -absent dynein arms in cilia, resulting in immotile cilia which causes respiratory problems and male infetility

an elastic protein that connects adjacent MT doublets in cilia

connect subunit A (of a preipheral doublet) to the central sheath in a cilia

• -where epithelial cells are held together at their apical ends
• -composed of 3 groups: Occluding (impermaeble), Anchoring (adhering) and communicating

• (1)zonula occludens/tight junctions
• -made up of TMP OCCLUDINS and CLAUDINS which are attched to actin filaments via ZO-1 (ZONULA CYTOPLASMIC PROTEINS)

(2)zonula adherens, (3)macula adherens (desmosome)

gap junction- direct cell to cell communications

act on occluding junctions resulting in permeable junctions

attacks zonula occludens in GIT causing massinve fluid movement into the lumen

targets ZO-1 and JAM of zonula occludens in the stomach, giving gastric ulcers

• attacks ZO-1 and ZO-2 of zonula occludens
• -also permanently activates Gs in cell, leading to increase cAMP, which leads to diarrhea

inhaled fecal pellats cause zonula occluden junction breakdown in the respiratory epithelim exposing lungs to allergans

• -continuous adhesive band that encirlce and hold cells together with a space of 15-20nm between calls
• -tmp E-CADHERINS bind with e/o on EC side, held together be a Ca++
• -IC- CATENIN, VINCULIN and ALPHA-ACTININ bind them to terminal web and actinin

• -localized sheer resistant 'spot welds'
• - IC disc- made of DESMOPLAKINS and PAKOGLOBINS which anchor to IF of cytokeratin
• -EC interlocking fingers made of Ca++ dependent DESMOCOLLINS and DESOMGLEINS, with a large space b/t cells= 30 nm
• - located in simple spithelia and stratified squamous

autoIg produced against desomsoma; proteins resulting in blistering

• -epithelia, CM and SM and neurons
• - 6 transmembrane 'connexins'= 1 connexon, that has a 2nm channel
• -open (dec pH or inc [Ca++]ic)
• -adjacent cells are only 2 nm apart

anchor actin filaments of cytoskeleton to the basement membrane

anchor IF to basement membrane

transmembrane proteins of the basal membrane

• mostly Coll 1
• fibers arranged in multiple directions
• few cells and little ground substance

• Coll 1 in parrallel bundles
• form ligaments etc

• broad flat tendons with mulitple layes aranged at 90 degrees to adjacent layer
• ** this arrangement is also found in the cornea**

• composed of tropocollagen molecules(3 alpha helix to form a triple helix) and make up fibers
• -stain with osmium and exhibit a transverse banding pattern

• 1- LCT and DCT, bone and dentine
• 2- hyaline and elastic cartilage (only form fibers)
• 3- reticular fibers (only forms fibers and fibrils)
• 4- basal lamina (densa) ONLY, (PRODUCED BY EPITHELIAL CELLS), keeps registration peptides

• gly-34
• pro-12
• hyp-10
• characteristic aa are hyp and hyl

on ends of procollagen that are essential for triple helix formation and keep the protein SOLUBLE inside the cell

• procollagen - reg. peptides = tropocollagen (insol)
• lys and hyl are cross-linked in adjacent tropocollagens

• -Coll 3, supportive meshwork
• -DO NOT FORM BUNDLES
• -produced by fibroblast, reticular cells and muscle cells(in vessels)
• -placed first in wound healing then replaced by Coll 1
• - PAS stains black b/c Ag loving

• Thymus has no reticular fibers
• -have cytoplasmic extensions that make up supportive structure (octopus)

defeciency in Coll 3 causing ruptures in arteries and LI, also characteristic stretchy skin

• -elastin core in a sheath of fibrillin microfilaments
• -elastin (gly and hyp rich, hyp poor, hyl absent) NOT COLLAGEN
• fibrillin- organizing center (glycoprotein), sensitive to UV radiation

absense of microfibrils during this process results in formation of elastin sheets (lamellae) as seen in the aorta

hold together elastic chains by cross linking lys residues, makeing it 5 x more extensible than rubber

mutation of fibrillin gene, a CT disorder, can cause arterial rupture due to only elastic sheet production and no fibrillin to hold

• composed of GAGs, proteoglycans and multiadhesive glycoproteins
• -act as microorganism barrier
• -permits diffusion

• -NO SO4
• -forms long chains that many proteoglycans will bind (noncovalently), which will attract Na+ and H2O
• -MADE IN THE PLASMA MEMBRANE

• -long straight polysaccharides of reapeating dissach.
• - amino sugar, uronic acid sugar (which has carboxyl)
• - high neg charge, which cause staining with basic dyes
• - high neg charge attracts Na+ and H2O= gel

• **All SO4ed GAGs link to a proteoglycan core**
• HLA
• Chondroitin 4-SO4
• Chondroitin 6-SO4
• Dermatan SO4
• Keraten SO4
• Heparan SO4
• Heparin

proteoglycan that links cells to EC matrix molecules

• present in all ground substance and on the surface of many cell types
• - can act as binding sites for GF and other signalling molecules

• proteoglycan with >200 GAGs, chondroitin SO4 and keratan SO4
• -**abundant in GS of cartilage and absorb lots of H2) giving it good resistance to compression**

proteoglycan with only a single GAG

a transmembrane proteoglycan

stabalize ECM by binding cell surface, collagen, proteoglycans and GAGs

main molecule in CT (dimer)

• secreted by S. aureus
• chops HLA in smaller pieces making it soluble and breaking down the ground substance, aiding rapid spread

fibroblasts, macrophage, mast and adipose cells

• feature of fibroblasts and SM cells
• found in wound healing (wound contraction) and the preiodontal ligament

• b cell derived
• -'clock face arrangement' due to alternating patches of hetero- and euchromatin
• -life span of 20-30 days

• -E-cadherins in the Zonula adherans
• -TMP that bind plaques to desmoplakins and apkoglobins of the desmosome (macula adherans)

anterograde(via kinesin): fast- synaptic vesicles, med- mtch, slow- proteins and actin

retrograde(vi dynesin)- fast- anything that needs to be degraded

• glial fibrillar acidic protein
• -unique to astrocytes (the largest of the glial cells)