Fig. 1.11
Download
1 / 39

Fig. 1.11 - PowerPoint PPT Presentation


  • 196 Views
  • Updated On :

Fig. 1.11. Nucleus: structure and function. Heterochromatin = too compacted, transcriptionally inactive. nuclear envelope. Nucleolus. Nucleoplasm. Euchromatin = can be transcriptionally active. Nuclear envelope and lamina. cytoplasm. N. lamina. Nuclear pore. heterochromatin.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Fig. 1.11' - lise


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Nucleus structure and function l.jpg
Nucleus: structure and function

Heterochromatin =

too compacted, transcriptionally inactive

nuclear envelope

Nucleolus

Nucleoplasm

Euchromatin = can be transcriptionally active


Nuclear envelope and lamina l.jpg
Nuclear envelope and lamina

cytoplasm

N. lamina

Nuclear

pore

heterochromatin



Lamins are filamentous proteins in the intermediate filament family l.jpg
Lamins are filamentous proteins in the intermediate filament family

Lamin phosphorylation in prophase disassembles the nuclear lamina & allows for nuc. envel. breakdown

Laminins are extracellular proteins, unrelated


Nuclear pore l.jpg
Nuclear pore family

  • nuclear localization signals (nuclear import signals)

  • nuclear export signals

  • highly regulated


Mitochondria on l.jpg
Mitochondria(on) family

outer

membrane

DNA

inner

membrane

matrix

cristae

ribosomes

ATP synthase


Inner membrane and matrix l.jpg

hi [H family+]

ATP

synthase

FADH2

NADH

Krebs

cycle

ATP4-

Antiporter

ADP3-

pyruvate

Inner Membrane and matrix

electron

transport

system

symporter

H+

P04-2


Endosymbiotic theory mitochondria are similar to prokaryotes l.jpg
Endosymbiotic theory: familyMitochondria are similar to prokaryotes

  • Own circular, naked DNA

  • Own ribosomes - similar to prokaryotic

    • e.g. sensitive to same inhibitors

  • Divide by fission

  • Double membrane suggests endocytosis


Lysosomes membranous organelles filled with digestive enzymes l.jpg
Lysosomes: familymembranous organelles filled with digestive enzymes

  • Breakdown endocytosed materials

    • Thru’ phagocytosis or receptor mediated endocytosis

  • Breakdown old organelles (residual body)

  • Acidic pH


Phagocytosis vs autophagy l.jpg
Phagocytosis vs. Autophagy family

Phagocytosis

lysosomes

Autophagy


Membrane trafficking l.jpg
Membrane trafficking family

  • RER to cis Golgi

  • Modified in Golgi (glycosylation, phosphorylation)

  • Sorted at trans Golgi network into

    • Lysosomal

    • Regulated

    • constitutive


Rough endoplasmic reticulum l.jpg

Ribosomes family

Synthesis of secreted and membrane proteins

Rough endoplasmic reticulum



Signal hypothesis signal peptide srp srp receptor translocon l.jpg
Signal hypothesis: signal peptide, SRP, SRP-receptor, translocon

SRP = signal recognition particle


Smooth er lipid synthesis detox ca 2 sequestration l.jpg
Smooth ER, lipid synthesis, detox, Ca translocon2+ sequestration


Golgi l.jpg
Golgi translocon



Protein modifications occur in steps in the golgi the extent of changes varies l.jpg

CIS & translocon

CGN

RER retrieval, PO4 on mannose,

mannose removal

mannose removal

N-acetylglucosamine addition

MEDIAL

TRANS

fucose and glucose addition

TGN

sialic acid addition, sorting

Protein modifications occur in steps in the Golgi. The extent of changes varies.


Glycosylation l.jpg
Glycosylation translocon

Karp, Fig. 8.20


Sorting at the tgn l.jpg
Sorting at the TGN translocon

constitutive

secretion

lysosomal

pathway

regulated

secretion

trans Golgi network




Phospholipids are most common in membranes l.jpg
Phospholipids are most common in membranes translocon

Polar

Head

Fatty

acid

tails




Fluidity means that lipids proteins can float in the membrane via diffusion l.jpg
Fluidity means that lipids (& proteins) can “float” transloconin the membrane via diffusion

Time


Three classes of membrane proteins transmembrane proteins a type of imp l.jpg
Three classes of membrane proteins: Transmembrane proteins (a type of IMP)

Oligosaccharides - always face out

Extracellular

domain (ECD)

OUT

Transmembrane

domain

Intracellular

domain (ICD)

IN


Three classes of membrane proteins lipid anchored membrane proteins imps l.jpg
Three classes of membrane proteins: Lipid-anchored membrane proteins (IMPs)

Covalently linked to a glycophospholipid.

E.G.: Normal cellular scrapie protein

& alkaline phosphatase

OUT

Covalently linked to fatty acid

E.G.: ras

IN


Three classes of membrane proteins peripheral membrane proteins pmps l.jpg
Three classes of membrane proteins: proteins (IMPs)Peripheral membrane proteins (PMPs)

OUT

IN

Or, PMPs could bind to specific lipid heads.

Specific interaction between IMP & PMP


Imps as a helix or b barrel l.jpg
IMPs as proteins (IMPs)a-helix or b-barrel


Selective permeability l.jpg
Selective permeability proteins (IMPs)



Four mechanisms by which solute molecules move across membranes l.jpg
Four mechanisms by which solute molecules move ACROSS membranes

Simple diffusion

across bilayer

Simple diffusion

thru channel

Facilitated

Diffusion thru’ passive transporters

Active

transport


Membrane potential affects molecular movement l.jpg
Membrane Potential Affects Molecular Movement membranes

A. neutral

No effect on inward transport

No effect on outward transport

B. cation

Favors inward transport

Opposes outward transport

C. anion

Opposes inward transport

Favors outward transport


Passive transport by channel proteins don t bind solute can be ligand voltage or stress gated l.jpg
Passive transport by membraneschannel proteins: don’t bind solute & can be ligand-, voltage-, or stress-gated


Passive transport by facilitated diffusion l.jpg
Passive Transport by Facilitated diffusion membranes

  • Solute binds transporter protein

  • So, transport is saturable



Active transport by the na k pump or atpase l.jpg
Active transport by the membranesNa/K pump or ATPase


ad