unexpected diversity in the innate immune system of the purple sea urchin l. courtney smith...
TRANSCRIPT
Unexpected Diversity in the Innate Immune
System of the Purple Sea Urchin L. Courtney SmithDepartment of Biological SciencesGeorge Washington UniversityWashington DC202-994-9211 Strongylocentrotus purpuratus
Deuterostomes
Protostomes
Animal Phylogenyand the
Evolution of Immunity
ArthropodsMolluscsAnnelids
Chordates Vertebrates
MammalsBirdsReptilesAmphibiansFishSharks & Rays
Agnathans Lampreys Hagfish
Protochordates Ascidians
Echinoderms Sea Urchins
Sea Urchin Genome Annotation Incomplete Complement System
Missing Classical and Terminal pathways Duplication of Alternative pathway
Large gene families Toll-like receptors, 222 gene models (humans have ~11)
expressed in coelomocytes (immune cells) NOD-like receptors, 203 gene models (humans have ~20)
expressed in gut Scavenger receptors, 218 gene models
expressed in coelomocytes C-type lectins, 408 gene models (humans have ~100)
encoding 108 small lectins, 300 mosaic proteins (Cohen & Smith, unpublished)
Hibino et al., Dev Biol 300:349, 2006TSUGSC, Science 314:941, 2006Rast et al., Science 314:952, 2006
Highly Diverse Innate Immune System
Of 1025 randomly chosen ESTs, 72% matched to two unknown sequences. EST333 (Smith et al., 1996) DD185 (Rast, Pancer & Davidson, 1999)
Bad sequence
UnknownSignal
transduction
Protein metabolism
Molecular transport
Nuclear activities
Protease activity
Metabolism
Defense
Cytoskeletal elements
185/333
All others
185/333
All others
Gene Expression in Sea Urchin Immune Cells Responding to LPS
Nair et al., Physiol Genomics 2005.
Alignment of 185/333 cDNAs
Terwilliger et al., Physiol Genomics 2006
300 nt
Gaps define blocks of sequence called elements.
Alternative splicing?
185/333 Gene Structure
407bp
Leader Elements 1 - 25E2
Quantitative PCR estimates 80 - 120 alleles per genome
Terwilliger et al., Physiol Genomics 2006
< 2 kb
Gene Element Patterns
Intron elements
Exon 1Exon 2 elements
Group
F
B
E
D
A
C
0
L#
1
28
1
4
3
1
1
1
1
2
1
3
5
2
5
1
1
1
12
1
1
1
1
14
1
6
1*
1
5*
2*
5*
2
7*
4*
3*
6*
6*
1
3b
3
3d
2*
1e
1c
1f
9*
7*
8*
6
2
3c
3f
Pattern
C
B
S
C
C
S
S
S
S
S
S
B
B
S
S
C
S
S
B
C
C
C
C
B
C
C
Source
300 bp
b
b
b
b
c
b
b
b
b
b
b
b
b
b
b
a
b
b
b
7 10 139 12
8 1511 1714 1916
23 2018 22 2521
24653 421
c
b
b
a
a
a
a
B
C
B
B
C
C
C
D
C
D
A
A
B
C
B
E
D
C
E
E
E
E
C
E
C
E
Int.
A
100 bp
BCD
E
1 542 3 6 7 8 9
Buckley & Smith, in prep
185/333 Sequence Diversity
Element diversity is a result of SNPs and indels
Sequences of identical genes are rarely identified within an individual sea urchin
Identical genes are never shared among sea urchins.
Some element sequences are shared among dissimilar genes
1
2
3
4
6
8
10
11
12
13
14
1 1
1 1
1
1 1
1
2
6
8
9
14
17
10
18
19
3
20
21
1
5
8
1
2
4
5
1
2
3
5
6
7
10
1
2
1
2
3
1
2
5
7
10
12
1
2
3
4
5
7
9
1
3
4
7
9
11
13
14
19
1
2
3
5
6
7
8
12
13
17
1
2
3
6
9
10
11
12
13
17
19
21
22
23
1
3
6
1
2
3
4
6
7
9
10
11
14
16
18
1
2
6
10
20
34
46
13
15
17
25
29
37
39
1
2
3
4
6
7
1
2
4
5
6
7
9
1
3
4
5
7
8
9
1
2
3
4
5
1
2
2
1
2
3
4
2
1
2
3
5
6
1
2
3
1
2
3
4
5
1
2
2
3
5
6
7
8
9
11
12
19
20
1
16
19
25
28
3
11
17
35
41
6
9
18
30
57
61
67
1
2
3
4
5
Element Scrambling 38 unique genes from animal 10
Buckley & Smith, in prep
L
Intron Elements
Exon 2 Elements
Conclusions Complex immune system Large gene families Unknown mechanisms for diversificationDo all metazoa have mechanisms for immune
diversification?
Future Problems 185/333 locus structure 185/333 protein function
AcknowledgmentsGeorge Washington University
David Terwilliger Katherine Buckley Virginia Brockton Rebecca Easley
Sea urchin immunology is supported by the National Science
Foundation
Medical Univ. of S. CarolinaPaul Gross
Macquarie UniversityDavid RaftosSham NairNolwen Dheilly
Dickinson CollegeJohn Henson
Duke UniversityTom KeplerSupriya Munshaw
Young-Ok KimHeather Del Valle Lindsay Edwards