Suitable strains of Manayunkia speciosa are required

Download Report

Transcript Suitable strains of Manayunkia speciosa are required

Genetic diversity of Manayunkia speciosa
in the Klamath River basin
By: Dan Horner
Mentors: Sascha Hallett
Jerri Bartholomew
Background
• Ceratomyxa shasta is a
microscopic, spore-forming
parasite
• Causes intestinal necrosis and
mortality of Klamath River
juvenile salmonids
• 60% of out migrating juvenile
salmonids infected
• Severe economical and
ecological impacts
Economic Effects of C. shasta
• Low salmon numbers
forced regulatory
closures of 2006 salmon
fishing
• Loss of $150 million
to the region's
economy
• Over $2 million spent
on C. shasta research
annually
Salmonid Populations
Salmonid species at risk:
- Steelhead
- Coastal cutthroat trout
- Coho salmon*
- Spring and fall-run chinook
*Classified as an endangered species in 1997(ESA) and 2002 (CESA)
C. shasta Lifecycle
Salmonid
Myxospore
Actinospore
M. speciosa
Intraspecies differences could affect the suitability of
this polychaete as the definitive host
Hypothesis
• Manayunkia speciosa in the Pacific
Northwest are the same species
Objective:
• Determine if Klamath River polychaetes belong
same species, and if so, determine if distinct
strains of M. speciosa exist within the Klamath
River Basin
Primary Locations of Research
Klamath
Lake
Iron Gate Dam
Willamette River
1. Acted as a necessary
outgroup for intraspecific
phylogenetic comparisons
Willamette
2. A known infectious zone for
C. shasta
3. 300 miles NW of primary
sample site, the Klamath.
4. Genetically isolated river
basin for comparison to the
Klamath
Klamath
Manayunkia
genetic background
• No genetic data exists for
M. speciosa
• However, Manayunkia spp. have
been sequenced from Lake Baikal
- M. sp.TP2002
- M. zenkewitschii
- M. athalasia
• All Manayunkia were sequenced
using universal primers targeting the
Cytochrome Oxidase c subunit 1
gene
Lake Baikal
Methods
1. Extract DNA from
collected samples
2. Specific CO1 gene
amplified through PCR
3. PCR product sequenced
and analyzed for novel
genetic characteristics
Cytochrome Oxidase
Subunit 1(CO1)
• CO1 gene:
- Subunit 1 is a 710 bp
mitochondrial gene
- Codes for 13 proteins
- Could possibly be used as a
universal barcode for all species
• For Nematodes:
- 0-6% variability: same species
- 10-20% variability: different species
Subunit 1
Species/Location
varianced-val
values
Amplified # Interspecies
d-val
d-val
bp
sp2002
zenk with known
athalasia
consistent
d-val
Willamette
species variability
Known species
M. athalasia
variability 675
M. sp2002
16%
22%
-
19%
19%
17%
-
576
M. zenkewitschii
565
20%
-
-
-
520
-
-
19%
-
505
-
-
19%
2.1%
-
-
19%
3.2%
Willamette
Williamson
I5 Site
530
Intraspecies variance also
within acceptable level
Current Genotypic Results
Klamath Genotypes
Willamette Genotypes
Klamath and Willamette
Conclusion
• All the Manayunkia used in
previous C. shasta research
have been the species,
Manayunkia speciosa.
• Distinct genotypes appear
to exist, but further
research is necessary
Ongoing Research
Hudson River, NY
Deschutes River, OR
Fraser River, B.C.
Cowlitz River, WA
Lake Superior, WI
Acknowledgements
•
•
•
•
•
•
•
•
•
•
Stephen Atkinson
Gerri Buckles
Charlene Hurst
Sarah Bjork
Jill Pridgeon
Sue-Jie Koo
Kevin Ahern
Jerri Bartholomew
Sascha Hallett
HHMI