Epstein-Barr Virus BGLF4 Kinase Induces Disassembly of the Nuclear - - PowerPoint PPT Presentation

▶
epstein barr virus bglf4 kinase induces disassembly of
SMART_READER_LITE
LIVE PREVIEW

Epstein-Barr Virus BGLF4 Kinase Induces Disassembly of the Nuclear - - PowerPoint PPT Presentation

Feb 08, 2024 340 likes •690 views

Epstein-Barr Virus BGLF4 Kinase Induces Disassembly of the Nuclear Lamina to Facilitate Virion Production Chung-Pei Lee et al . Journal of Virology, 82 :11913-11926, 2008. Speaker: Shiang-Yuan Hsieh Advisor: Li-Kwan Chang, PhD Date: 2008.11.25

slide-1
SLIDE 1

1

Epstein-Barr Virus BGLF4 Kinase Induces Disassembly of the Nuclear Lamina to Facilitate Virion Production

Chung-Pei Lee et al. Journal of Virology, 82:11913-11926, 2008.

Speaker: Shiang-Yuan Hsieh Advisor: Li-Kwan Chang, PhD Date: 2008.11.25

slide-2
SLIDE 2

2

Epstein-Barr Virus

γ-herpesvirus human herpesvirus 4(HHV4) Enveloped virus Linear ds DNA, ~180 kb Tissue tropism: B cells, T cells and epithelial cells

  • Dr. Chang LK ppt
slide-3
SLIDE 3

3

Epstein-Barr Virus Life Cycle

Latency proteins: EBNAs LMPs

Latency Stage Lytic Stage

Spontaneous activation Stress(heat shock, UV) TPA/Sodium butyrate Anti-IgG

Immediate-early proteins Early proteins Late proteins

slide-4
SLIDE 4

4

Epstein-Barr Virus Associated Diseases

Direct: Infectious mononucleosis(IM) Relative: Hodgkin’s disease(HD) Burkitt’s lymphoma(BL) Post transplant lymphoproliferative disorder (PTLD) Nasopharyngeal carcinoma(NPC)

slide-5
SLIDE 5

5

EBV Lytic Cycle

Immediate-early genes

Rta, Zta

Early genes

BMRF1, BALF5, BALF2, BGLF4…etc

Late genes

BFRF1, BFLF2…etc Transactivation DNA replication Package, Release, membrane protein

slide-6
SLIDE 6

6

slide-7
SLIDE 7

7

EBV nucleocapsid NPC ONM INM

38 nm 120 nm

slide-8
SLIDE 8

8

Primary Envelopment

slide-9
SLIDE 9

9

The Cell: A Molecular Approach, 4e

Nuclear Membrane

ONM INM NPC

slide-10
SLIDE 10

10

Nuclear Lamina

A electro-dense meshwork lining the INM (nucleoplasmic face) Composed by lamin A, B1, B2, C Provide structural support for nuclear membrane

Aebi et al., Naure. 1986

slide-11
SLIDE 11

11

Nuclear Lamina

Bind to many INM proteins (emerin, lamin B receptor) Bind to chromatin, DNA replication complex

Goldman et al., Genes Dev. 2002

slide-12
SLIDE 12

12

Lamin

Type-V intermediate filament A type: lamin A, C(lmnA) nuclear stiffness B type: lamin B1, B2(lmnB1, B2) fundamental structure of lamina nuclear shape

Head Rod Tail

ONM INM Lamin B Lamin A/C

slide-13
SLIDE 13

13

Lamin assembly

The Cell: A Molecular Approach, 4e

slide-14
SLIDE 14

14

Nuclear lamina disassembly in M phase

Cdc2

(CDK1)

Molecular Biology of the Cell, 5e

The author assume that BGLF4 mimic Cdc2 function.

slide-15
SLIDE 15

15

EBV BGLF4 kinase

EBV early gene during lytic cycle Ser/Thr protein kinase Belong to the conserved family of herpesviral UL kinases Substrate:

  • BGLF4, BMRF1, EBNA-2, EBNA-LP, Zta
  • EF-1δ, condensin, topoisomerase II, MCM4

BGLF4 phosphorylates EF-1δ at Cdc2 target sites.

Kawaguchi, Y. et al. (2003). J Virol 77:2359-68

slide-16
SLIDE 16

16

slide-17
SLIDE 17

17

Aims

Determine how EBV BGLF4 kinase regulates the dynamics of the nuclear lamina. Explore the mechanism used by BGLF4 to regulate the egress of nucleocapsid.

slide-18
SLIDE 18

18

slide-19
SLIDE 19

19

BGLF4 induces nuclear lamina disassembly?!

slide-20
SLIDE 20

20

BGLF4 interacts with lamin A/C and induces nuclear lamina disassembly

IFA (Immunofluorescence assay) Co-IP (Co-immunoprecipitation assay) HeLa cells Immunofluorescence assay (Confocal microscopy)

Kinase dead mutant

slide-21
SLIDE 21

21

BGLF4 phosphorylates lamin A in vitro

Immunoprecipitation(IP) kinase assay HeLa cells

BGLF4 phosphorylates EF-1δ at Cdc2 target sites. Kawaguchi, Y. et al. (2003). J Virol 77:2359-68

Cdc2 (CDK1)

slide-22
SLIDE 22

22

Ser-22,390,392 of lamin A are important for BGLF4-induced nuclear lamina disassembly

HeLa cells IFA(Confocal)

slide-23
SLIDE 23

23

Ser-22,390,392 of lamin A are important for BGLF4-induced nuclear lamina disassembly

slide-24
SLIDE 24

24

Would nuclear lamina be disassembled by BGLF4 during EBV lytic cycle? Conclusion(1/3)

BGLF4 phosphorylates lamin A/C and induces nuclear lamina disassembly. Ser-22,390 and 392 of lamin A are important for BGLF4-induced nuclear lamina disassembly.

slide-25
SLIDE 25

25

BGLF4 induces nuclear lamina disassembly during EBV reactivation

EBV(+) EBV(-)

slide-26
SLIDE 26

26

BGLF4 induces nuclear lamina disassembly during EBV reactivation

Knockdown BGLF4!!!

slide-27
SLIDE 27

27

What are the effects of nuclear lamina disassembly on the EBV virion production? Conclusion(2/3)

Nuclear lamina can be disassembled by BGLF4 during EBV reactivation.

slide-28
SLIDE 28

28

Effects of nuclear lamina disassembly

  • n the EBV virion production

EREV8 cells

Immediate-early protein Early protein Late protein

slide-29
SLIDE 29

29

Effects of nuclear lamina disassembly

  • n the EBV virion production

EREV8 cells

Early protein Late protein Late protein

slide-30
SLIDE 30

30

EBV late protein BFRF1, BFLF2

EBV late gene Primary envelope proteins BFRF1cytoplasm BFLF2nuclear

Nucleo- capsid Nucleo- capsid Nucleo- capsid

BFRF1 BFLF2 INM ONM

Primary Envelopment

Nucleus Cytoplasm

slide-31
SLIDE 31

31

Lamin A mutant reduce the expression of EBV late gene BFRF1/BFLF2

EREV8 cells

slide-32
SLIDE 32

32

Lamin A mutant reduce virion production

EREV8 cells PCR

slide-33
SLIDE 33

33