Eukaryotic Cell Physical Compartments

Cell NucleusFrom CellBiology

IntroductionThis lecture introduces the nucleus and how information is transferredfrom stable stored information (DNA) converted to an intermediate(mRNA, rRNA, tRNA) of variable stability, exported from the nucleus tothe cytoplasm where mRNA is then translated into Protein. This is geneexpression, the products of this process are used either within the cell,exported (exocytosis) or used to replace worn out components.

We will study this topic looking at the key organelle in this process, thenucleus.

Nucleolar Assembly Movie | Movie - nuclear pore complexes(http://jcb.rupress.org/cgi/content/full/154/6/1147/FIG6/DC1)

Lecture Archive: 2016 (https://cellbiology.med.unsw.edu.au/cellbiology/index.php?title=Cell_Nucleus&oldid=58799) | 2016 PDF | 2015(https://cellbiology.med.unsw.edu.au/cellbiology/index.php?title=Cell_Nucleus&oldid=51902) | 2014(http://php.med.unsw.edu.au/cellbiology/index.php?title=Cell_Nucleus&oldid=48075) | 2013(http://php.med.unsw.edu.au/cellbiology/index.php?title=Cell_Nucleus&oldid=42432) | 2010 | 2009 | 2008 Online content(http://cellbiology.med.unsw.edu.au/units/science/lecture0804.htm)

MH - note that content listed below will not match exactly current lecture structure but has been selected as having similar content.

ObjectivesUnderstand the concept of the cell nucleusUnderstand the overall structure and components within the nucleusUnderstand the functions of the nucleusBrief understanding of chromosomal structure

EukaryotesDifference between Prokaryotes and Eukaryotes

CytoskeletonDNA structure

circular, linearPacking (histones)RNA processing (splicing)

Eukaryote Gene Expression

DNA -> mRNA -> Protein

DNA (transcription) -> mRNA (translation) -> Protein (function)

TranslationPage | Play

rough endoplasmic reticulum (tem)

Nucleus Membrane Evolution

Nuclear envelope and endoplasmic reticulum system

Nucleus

DNA (transcription) -> mRNA Nuclear processing (export)

DNA -> mRNA splicing (introns removed, exons joined) -> mRNA

Cytoplasm

mRNA (translation by ribosomes) -> Protein (processing)

Protein Processing cytoplasm (free ribosomes), rough endoplasmic reticulum(bound ribosomes)

Some proteins are returned to the nucleus by a Nuclear Localization Sequence (NLS)

SV40 Large T-antigen (http://www.plosone.org/article/fetchObject.action?uri=info:doi/10.1371/journal.pone.0010475.g001&representation=PNG_M) - PKKKRKV (single part)nucleoplasmin - KR[PAATKKAGQA]KKKK (two part) two clusters of basic amino acids separated by 10 amino acids.

Membrane EvolutionPostulated that an early "coating" structure lead to the infolding of the primitive plasmamembrane to form the many membrane covered organelles in the cytoplasm.

These modules may also be the evolutionary precursor to the nuclear pore structures andaccount for the double membrane that coats the nucleus.

Nuclear CompartmentNuclear envelopeNuclear cytoskeletonNucleolusChromosome territories

Euchromatin is a lightly packed form of chromatin (DNA, RNA and protein)Heterochromatin is a tightly packed form of DNA

Interchromatin compartment“speckles” interchromatin granule clusters

Splicing speckles or SC 35 domainsthought to be sites of storage of mRNA splicing factors

nuclear bodies - Cajal and PML

Links: MBOC - A cross-sectional view of a typical cell nucleus(http://www.ncbi.nlm.nih.gov/books/NBK26821/?rendertype=figure&id=A606)

Nucleus Size

cell "karyoplasmic ratio" relatively constant (ratio of nuclear volume to cell volume)most other cellular organelles (ER and mitochondria) can vary greatly inamounts

multinucleated fission yeast cellsrelative amount of cytoplasm surrounding each nucleus controls the size ofindividual nuclei

Links: Nuclear size control in fission yeast. Neumann FR, Nurse P. J Cell Biol. 2007 Nov19;179(4):593-600. PMID: 17998401 (http://www.ncbi.nlm.nih.gov/pubmed/17998401)

Nuclear EnvelopeForms structural compartmentNuclear envelope two concentric membranesBreaks down each mitosis (recycled)Outer membrane continuous with Endoplasmic Reticulum (Endoplasmic Reticulum is covered in Lecture 5)Contains holes “nuclear pores”

Nuclear architecture

The Cell - Figure 8.1. The nuclear envelope (http://www.ncbi.nlm.nih.gov/books/bv.fcgi?highlight=nuclear%20envelope&rid=cooper.figgrp.1325)

Nuclear Cytoskeleton

The nuclear cytoskeleton has 2 layers

outer - less organised surrounds nuclear envelopeinner - nuclear lamina - thin shell (20 nm) underlying the nuclear envelope

associates with both the inner nuclear membrane and underlying chromatincan regulate gene expressionprovides anchor sites for nuclear pore complexesbroken down each cell division

Neural Development - Movie - Nucleus position within the cell is a signal for neural fate(https://embryology.med.unsw.edu.au/embryology/index.php/Interkinetic_Nuclear_Migration_Movie).

Cytoplasmiccytoskeleton migratingneuron

Nuclear pores (red)cytoskeleton (green)chromatin (blue)

Nuclear Lamin A

Lamin B1 in mitosis

Nuclear lamins andsplicing factors

Nuclear Envelope showing underlying nuclearmatrix (green) (EM Image Martin Goldberg)

Muscle satellite celllamin A/C expression

heterochromatin (green)LaminA/C (red)[1]

Links: MBOC - A cross-sectional view of a typical cell nucleus (http://www.ncbi.nlm.nih.gov/books/NBK26821/?rendertype=figure&id=A606)

Nuclear Lamins

Intermediate filaments covered in Cytoskeleton Lecture – Intermediate Filaments

Lamins - Class V intermediate filamentsVertebrate lamins are classified into 2 types - A and B10 nm in diameter, forms rope-like networkspolypeptide form dimers - central alpha-helical regions of two polypeptide chainsare wound around each otherassembly - head-to-tail association of dimers form linear polymers, side-by-sideassociation of polymers form filamentsB-type - B1 and B2 (586 aa protein, Mr 66,334 Da) lamins are ubiquitouslyexpressed throughout developmentA-type - lamins A and C (Mr 74 kD and 65 kD) lamins in many organismsexpression does not appear until midway through embryogenesis (possible role indifferentiation)lamins phosphorylation state affects nuclear envelope assembly state(dephosphorylation nuclear envelope assembly, phosphorylation nuclear envelopedisassembly)Lamins also link DNA to nuclear envelope (Lamin B1 interacts with chromatin)

Lamin APage | Play

Nuclear lamina and lamina-interactingproteins

Nucleoskeleton to the cytoskeletoncomplexes

Lamin Abnormalities - (laminopathies) mutations in lamins can lead to human disease (Hutchinson-Gilford Progeria Syndrome)

Links: MBOC - A cross-sectional view of a typical cell nucleus (http://www.ncbi.nlm.nih.gov/books/bv.fcgi?&rid=mboc4.figgrp.606) |Nature Medicine - Image - The nuclear membranes include the interconnected but distinct inner and outer nuclear membranes and the nuclearpore membrane (http://www.nature.com/nm/journal/v6/n2/fig_tab/nm0200_136_F1.html) MBOC - The breakdown and re-formation of thenuclear envelope during mitosis (http://www.ncbi.nlm.nih.gov/books/bv.fcgi?&rid=mboc4.figgrp.2174) | The Cell - Intermediate FilamentProteins (http://www.ncbi.nlm.nih.gov/books/bv.fcgi?&rid=cooper.table.1810) | The Cell - Model of lamin assembly(http://www.ncbi.nlm.nih.gov/books/bv.fcgi?&rid=cooper.figgrp.1328) | Abcam - Lamin B1 antibody - Nuclear Envelope Marker(http://www.abcam.com/index.html?datasheet=16048#ab16048-IF-Im1.jpg) | OMIM - Lamin A/C(http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=150330) | OMIM - Lamin B1 (http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=150340) |

Nuclear Transport History

1999 Nobel Prize Medicine - Günter Blobel for the discovery that "proteins have intrinsic signals that govern their transport and localizationin the cell"

Links: 1999 Nobel Prize Medicine - Günter Blobel (http://nobelprize.org/nobel_prizes/medicine/laureates/1999/press.html)

Nuclear Pores

Nuclear pore complex

Protein complexExternal diameter of about 120 nm (30 times the size of a ribosome)Channel diameter 25 nmchannels between nucleus and cytoplasm (import/export)passive passage of small polar molecules, ions, (<40-60 kDa)active (selective/ regulated) passage of larger macromolecules, proteins and RNAsimportin - cytosolic protein

Nuclear pore EM structure timeline[2]

Movie - NPC movement in interphase

Links: JCB Movie - Nuclear Pore Complex movement in interphase(http://jcb.rupress.org/content/suppl/2001/07/11/200101089.F4.DC1)

Nuclear BodiesFunctional compartments

Nucleus Movie 1

Cajal Bodies

also called - nucleolar accessory bodies, coiled body, gems0.1 - 2.0 microns, 1-10/ nucleusGems and Cajal bodies two forms of same structureGEMS (Gemini of coiled bodies)

proposed sites where small nuclear ribonucleoproteins (snRNPs) and small nucleolar RNAs (snoRNPs) are modified.snRNPs are particles that combine with pre-mRNA and various proteins to form spliceosomessnoRNAs are a class of small RNA molecules that are involved with modifications of ribosomal RNAs (rRNAs) and other RNAgenes

Cajal bodies were first reported in 1903 by the Spanish cytologist/histologist Ramón y Cajal, who christened them "nucleolar accessorybodies".

Cajal, S.R. 1903. Un sencillo método de coloración selectiva del retículo protoplásmico y sus efectos en los diversos órganos nerviosos devertebrados e invertebrados. Tra. Lab. Invest. Biol. 2:129–221.

See also Nature Reviews - The centennial of the Cajal body

PML Bodies

promyelocytic leukaemia nuclear bodiesalso called PODs, ND10 or Kremer bodiesFunction unknown

regulation of diverse cellular functions?viral infection, cellular transformation, innate immunity, growth control, apoptosisdynamic hubs sensing stress and DNA damage

Chromosomesnot “visible” at interphase, condense for mitosis (1,000 fold)

condensation allows chromosomes to move along mitotic spindle without breaking or tanglingeukaryotes have separate chromosomes

Human 23 pairs, 22 autosome pairs, 2 sex chromosomesdiploid 2 copies of each chromosome (inherited one male/one female)

except male sex chromosomes X from mother Y from fatherDNA and proteinpacking of DNADNA structureencodes genome (humans 30,000 genes, draft sequence published in 2001)DNA genes encode RNA and proteinsDNA can also encodes nothing

Chromosome Territories

Space within the nucleus occupied by individual chromosomesSeveral different models as to how these territories interact

Intrachromosomal domains possibly RNA processing and transport

Links: MBOC - Selective painting of two interphase chromosomes in a human peripheral lymphocyte(http://www.ncbi.nlm.nih.gov/books/bv.fcgi?&rid=mboc4.figgrp.686) | The Cell - Chromosome Territories(http://www.ncbi.nlm.nih.gov/books/bv.fcgi?&rid=cooper.figgrp.1352)

Nucleolus

Appearance

Fibrillar center, dense fibrillar component, and granular componentNucleolus changes during the cell cycle:

during mitosis - nucleolus breaks up as chromosomes condenseafter mitosis - nucleolus reforms from coalesce of tips of 10 chromosomes

Function

Sites of ribosomal (rRNA) gene transcription, processing, and ribosome assemblyNucleolus size depends on cell metabolic activitySites of ribosomal (rRNA) gene transcription, processing, and ribosome assemblyAll cells contain multiple copies of rRNA genes

Links: Movie - Dynamics of nucleolus-derived foci throughout the cytoplasm and the disappearance of NDF during telophase(http://jcb.rupress.org/content/suppl/2000/08/03/150.3.433.F2.DC1) | Movie - Dynamics of nucleolar reassembly in telophase wereanalyzed by the visualization of fibrillarin-GFP (http://jcb.rupress.org/content/suppl/2000/08/03/150.3.433.F3.DC1)

Chromosome Features

2 telomeres, centromere, replication originsTelomere- at ends of chromosome (bacterial DNA circular)Centromere- holds duplicated DNA togetherKinetochore - protein complex forms around the centromere forms during mitosisChromatin - DNA packed by DNA binding proteins (histones and non-histones) form 30nm DNA fibre2 types of chromatin in interphase nuclei (based on cytology)

heterochromatin - highly condensed (restricted gene transcription)euchromatin - less condensed (gene transcription)

Telomere

at ends of all chromosomes (not bacterial DNA circular)roles in chromosome replication and maintenancereplication

for replicating the ends of linear chromosomesmaintenance

proposed to provide each cell with a replication counting mechanism that helps prevent unlimited proliferationeach cell division shortens telomere 50–100 nucleotidesDNA 100s to 1,000s repeats of a simple-sequence containing clusters of G residues (humans AGGGTT)Telomerase enzyme maintains length

Centromere

directs movement of each chromosome into daughter cells every time a cell dividescentromere embedded in heterochromatinsatellite DNA sequences (AT-rich) repeated many thousands of timesproteins assemble on this to form Kinetochore

attachment site for spindle microtubules

Links: MBOC - Centromere (http://www.ncbi.nlm.nih.gov/books/bv.fcgi?&rid=mboc4.figgrp.672)

Replication Origins

Chromosome-condensation

DNA replication initiates at multiple origins (ori)in both prokaryotic and eukaryotic DNAmultiple origins in eukaryotes (human genome about 30,000 origins)each origin produces two replication forks (moving in opposite directions)

Chromosome DNA Packing

Euchromatin ("good chromatin") - light, transcriptionally active, about 10% of allchromatin.

Heterochromatin - condensed, transcriptionally inactive, about 90% of all chromatin.

Nucleosomes

formed by DNA wrapped around histonesunit particle of chromatin (nucleosomal histones) (discovered 1974)EM unfolded DNA has "beads on a string" appearancesecond order folding forms 300 nm fibrecondensed DNA for mitosis 700 nm fibre

Histones

only in eukaryotessmall proteins positively charged (binds negatively charged DNA)not sequence specific binding (as in transcription factors)4 core histones (H2A, H2B, H3, and H4)2 linker histones (H1/H5)

Abnormalities

Hutchinson-Gilford Progeria Syndrome

In more than 80% of cases the gene defect responsible for HGPS is a single spontaneous mutation in codon 608 of the LMNA gene,which encodes both lamin A and lamin C

Nucleosome

Hutchinson-Gilford_Progeria_Syndrome

Lamin A EM - normal and KO

single-base substitution in exon 11 that reveals a cryptic splice site in the LMNAgene thus producing a truncated proteinprogerin is a mutant form of the nuclear architectural protein lamin A

Emery-Dreifuss Muscular Dystrophy

OMIM - LAMIN A/C; LMNA (http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=150330)

Loss of a-Type Lamin Expression Compromises Nuclear Envelope Integrity Leading toMuscular Dystrophy (http://jcb.rupress.org/cgi/content/abstract/147/5/913)

Eukaryote Gene ExpressionDNA -> mRNA -> Protein

DNA (transcription) -> mRNA (translation) -> Protein (function)

DNA -> mRNA splicing (introns removed, exons joined) -> mRNA

DNA -> rRNA, tRNA, siRNA (RNA interference (RNAi) pathway

Nucleus DNA (transcription) -> mRNA Nuclear processing (export) Cytoplasm mRNA(translation) -> Protein (cytoplasm, rough endoplasmic reticulum)

Protein Modification

Protein - cytoplasmic (free ribosomes), rough endoplasmic reticulum (bound ribosomes)

Exocytosis

Rough Endoplasmic Reticulum -> transport vesicle -> Golgi apparatus -> secretoryvesicle

HistoryBelow are some example historical research finding related to cell junctions from the JCBArchive (http://jcb.rupress.org/misc/fromthearchive.shtml) and other sources.

1961 The nucleolar origin of rRNA (http://jcb.rupress.org/cgi/content/full/168/4/524-a)Base compositions and half-lives suggest to Jan-Erik Edström that the nucleolus is thesource of rRNA.

References1. Neveen A Hosny, Mingying Song, John T Connelly, Simon Ameer-Beg, Martin M

Knight, Ann P Wheeler Super-resolution imaging strategies for cell biologistsusing a spinning disk microscope. PLoS ONE: 2013, 8(10);e74604 PubMed24130668 | PLoS One.(http://www.plosone.org/article/info:doi/10.1371/journal.pone.0074604)

2. Alexander von Appen, Martin Beck Structure Determination of the Nuclear PoreComplex with Three-Dimensional Cryo electron Microscopy. J. Mol. Biol.:2016; PubMed 26791760

Textbooks

Molecular Biology of the Cell (4th ed.) - Part 1 Chapter 8 - The Cell Nucleus -Three views of a cell membrane (http://www.ncbi.nlm.nih.gov:80/books/bv.fcgi?db=Books&rid=mboc4.figgrp.1862)Molecular Cell Biology - The Dynamic Cell(http://www.ncbi.nlm.nih.gov:80/books/bv.fcgi?db=Books&rid=mcb.chapter.145)The Cell- A Molecular Approach - An Overview of Cells and Cell Research (http://www.ncbi.nlm.nih.gov:80/books/bv.fcgi?db=Books&rid=cooper.chapter.89)

Search Online Textbooks

"cell nucleus" Molecular Biology of the Cell (http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=cell+nucleus+AND+mboc4%5Bbook%5D) | Molecular Cell Biology(http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=cell+nucleus+AND+mcb%5Bbook%5D) | The Cell- A molecular Approach(http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=cell+nucleus+AND+cooper%5Bbook%5D)"nuclear envelope" Molecular Biology of the Cell (http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=nuclear+envelope+AND+mboc4%5Bbook%5D) | Molecular Cell Biology(http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=nuclear+envelope+AND+mcb%5Bbook%5D) | The Cell- A molecular Approach(http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=nuclear+envelope+AND+cooper%5Bbook%5D)"nuclear pore" Molecular Biology of the Cell (http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=nuclear+pore+AND+mboc4%5Bbook%5D) | Molecular Cell Biology(http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=nuclear+pore+AND+mcb%5Bbook%5D) | The Cell- A molecular Approach(http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?db=Books&cmd=search&doptcmdl=DocSum&term=nuclear+pore+AND+cooper%5Bbook%5D)

Books

The Cytoskeleton - cellular architecture and choreography (http://books.google.com/books?id=JNHuxHzTm7IC)

Reviews

Selma Osmanagic-Myers, Thomas Dechat, Roland Foisner Lamins at the crossroads of mechanosignaling. Genes Dev.: 2015, 29(3);225-37PubMed 25644599

Katherine L Wilson, Scott C Dawson Evolution: functional evolution of nuclear structure. J. Cell Biol.: 2011, 195(2);171-81 PubMed22006947

Michael D Huber, Larry Gerace The size-wise nucleus: nuclear volume control in eukaryotes. J. Cell Biol.: 2007, 179(4);583-4 PubMed17998404

Roderick Y H Lim, Ueli Aebi, Birthe Fahrenkrog Towards reconciling structure and function in the nuclear pore complex. Histochem.Cell Biol.: 2008, 129(2);105-16 PubMed 18228033

Articles

Wenjing Li, Brian J Ferguson, Walid T Khaled, Maxine Tevendale, John Stingl, Valeria Poli, Tina Rich, Paolo Salomoni, Christine J WatsonPML depletion disrupts normal mammary gland development and skews the composition of the mammary luminal cell progenitorpool. Proc. Natl. Acad. Sci. U.S.A.: 2009, 106(12);4725-30 PubMed 19261859

J Ellenberg, E D Siggia, J E Moreira, C L Smith, J F Presley, H J Worman, J Lippincott-Schwartz Nuclear membrane dynamics andreassembly in living cells: targeting of an inner nuclear membrane protein in interphase and mitosis. J. Cell Biol.: 1997, 138(6);1193-206 PubMed 9298976

L Yang, T Guan, L Gerace Integral membrane proteins of the nuclear envelope are dispersed throughout the endoplasmic reticulumduring mitosis. J. Cell Biol.: 1997, 137(6);1199-210 PubMed 9182656

AcronymsAA - amino acidDNA - deoxyribonucleic acidEM - electron microscopyFL - flourescentGEMS - Gemini of coiled bodiesINM - inner nuclear membraneKASH - Klarsicht/ANC-1/Syne-1 homology domain–containing proteinLEM domain - fold identified in LAP2, emerin, and MAN1 confers direct binding to dsDNALINC - nucleoskeleton to the cytoskeleton complexesmRNA - messenger RNANE - nuclear envelope

Moodle(http://moodle.telt.unsw.edu.au/course/view.php?id=18930)

NES - nuclear export signalNLS - nuclear localization signalNPC - nuclear pore complexNUP - nucleoporinONM - outer nuclear membraneOMIM - Online Mendelian Inheritance in Man DatabasePML Bodies - promyelocytic leukaemia nuclear bodiesRER - rough endoplasmic reticulumRNA - ribonucleic acidrRNA - ribosomal RNASER - smooth endoplasmic reticulumSUMO - small ubiquitin-related modifierSUN - Sad1/UNC-84tRNA - transfer RNA

MoviesNote - JCB has reorganised their website and some of the associated links. Also their Quicktime movies have not been updated and may notplay on current browsers.

Nuclear pore complexes are fixed in place Daigle et al. (http://jcb.rupress.org/cgi/content/abstract/154/1/71) report that nuclear porecomplexes (NPCs) undergo limited movements (http://jcb.rupress.org/cgi/content/full/200101089/F4/DC1) that match the deformationsof the nuclear envelope as tracked using a grid (http://jcb.rupress.org/cgi/content/full/200101089/F4/DC2) of bleached nuclear lamins.NPCs are therefore remarkably stable complexes, and are probably anchored to a protein network in the nuclear envelope.

Long term FRAP of POM121 - transmembrane nucleoporinLong term FRAP of lamina B1NPC movement in interphaseLamina elasticity (not visible after conversion?)

Nucleoporins reassemble around post-mitotic chromatin A conserved nuclear pore subcomplex was characterized and tracked byBelgareh et al. (http://jcb.rupress.org/cgi/content/abstract/154/6/1147), who found that the proteins were recruited(http://jcb.rupress.org/cgi/content/full/154/6/1147/FIG6/DC1) during telophase in a rim pattern surrounding the chromosomes. A lowlevel of staining was also apparent on the kinetochores throughout mitosis.

Nucleolar re-formation after mitosis Savino et al. (http://jcb.rupress.org/cgi/content/abstract/153/5/1097) follow the re-formation(http://jcb.rupress.org/cgi/content/full/153/5/1097/F3/DC1) of nucleoli after mitosis. Prenucleolar bodies (PNB) form on thechromosome surface and nucleolar material flows along links between PNBs(http://jcb.rupress.org/cgi/content/full/153/5/1097/F4/DC2) and towards (http://jcb.rupress.org/cgi/content/full/153/5/1097/F6/DC1) adeveloping nucleolar organizer region (http://jcb.rupress.org/cgi/content/full/153/5/1097/F4/DC1) (NOR). Eventually this leads to thefusion (http://jcb.rupress.org/cgi/content/full/153/5/1097/F9/DC1) of nucleoli to form a single entity.

Processing complexes may help reassemble nucleoli Nucleolar reassembly (http://jcb.rupress.org/cgi/content/full/150/3/433/F3/DC2)during telophase is shown by Dundr et al. (http://jcb.rupress.org/cgi/content/abstract/150/3/433) to require mitotically preservedprocessing complexes.

Speckles - A splicing factor has limited mobility Based on the limited mobility(http://jcb.rupress.org/cgi/content/full/150/1/41/F1/DC1) of a splicing factor, Kruhlak et al.(http://jcb.rupress.org/cgi/content/abstract/150/1/41) determine that the factor undergoes frequent but transient interactions withrelatively immobile nuclear binding sites, both when associated with speckles and when dispersed in the nucleoplasm. This a 3-D videothat should be viewed using red/green 3-D glasses.

2016 Course ContentLectures: Cell Biology Introduction | Cells Eukaryotes and Prokaryotes | Cell Membranes and Compartments | CellNucleus | Cell Export - Exocytosis | Cell Import - Endocytosis | Cytoskeleton Introduction | Cytoskeleton -Microfilaments | Cytoskeleton - Microtubules | Cytoskeleton - Intermediate Filaments | Cell Mitochondria | Cell Junctions| Extracellular Matrix 1 | Extracellular Matrix 2 | Cell Cycle | Cell Division | Cell Death 1 | Cell Death 2 | Signal 1 | Signal2 | Stem Cells 1 | Stem Cells 2 | Development | 2016 Revision

Laboratories: Introduction to Lab | Microscopy Methods | Preparation/Fixation | Cell Knockout Methods | CytoskeletonExercise | Immunochemistry | Project Work | Confocal Microscopy | Tissue Culture | Stem Cells Lab | Microarray Visit

2016 Projects: Group 1 | Group 2 | Group 3 | Group 4 | Group 5 | Group 6 | Group 7

Dr Mark Hill 2015, UNSW Cell Biology - UNSW CRICOS Provider Code No. 00098G

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