Peaks and valleys of prolactin-driven
gene expression during parental care
Dr. Rayna M. Harris
raynamharris
Postdoc, UC Davis
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Meet the co-authors (*here at SICB)
Dr. Rayna Harris
Dr. Suzanne Austin
Dr. Andrew
Lang
Dr. Matthew MacManes
Dr. Rebecca
Calisi
Rechelle Viernes
Dr. Jesse Krause
April Booth
Victoria Farrar
University of California, Davis University of New Hampshire
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*
Funded by NSF IOS-Animal Behavior.
We are grateful to the members of our labs and and the labs of John Wingfield and Titus Brown lab for discussion. 2
*
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Like humans, Rock Doves are bi-parental.
However, both male and female Rock Doves lactate.
Image by Victoria Farrar
Calisi & a Working Group of
Mothers in Science 2018 PNAS 3
Calisi 2018 Science
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What molecular profiles characterize parental care
transitions in the reproductive axis (HPG) of
bi-parental Rock Doves?
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https://github.com/macmanes-lab/DoveParentsRNAseq
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Experimental design for characterizing HPG gene
activity over the course of bi-parental care.
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https://github.com/macmanes-lab/DoveParentsRNAseq
N= 12 per group
576 RNA-seq
samples
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What explains the
most variation in
gene expression?
Tissue, sex, or
treatment?
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https://github.com/macmanes-lab/DoveParentsRNAseq
Kallisto -> Limma -> Rtsne or PCA
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Gene expression in
each tissue is quite
distinct.
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https://github.com/macmanes-lab/DoveParentsRNAseq
Kallisto -> Limma -> Rtsne or PCA
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Sex differences are
most pronounced in
the gonads.
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https://github.com/macmanes-lab/DoveParentsRNAseq
Kallisto -> Limma -> Rtsne or PCA
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https://github.com/macmanes-lab/DoveParentsRNAseq
Treatment effects are
most pronounced in
the pituitary.
Kallisto -> Limma -> Rtsne or PCA
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What gene
explains the most
variation?
Prolactin.
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https://github.com/macmanes-lab/DoveParentsRNAseq
PC loadings calculated and visualized
with `factoextra`
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Confirms that prolactin is an
important regulator of reproductive
axis and parental care behavior.
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Levels of prolactin,
in the the blood are
correlated with
prolactin (PRL)
expression in the
pituitary.
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https://github.com/macmanes-lab/DoveParentsRNAseq
DESeq2: pituitary only, treatment * sex
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Imagine PRL
expression as a
song.
What genes
work in concert
to create a
“transcriptional
symphony”?
https://github.com/macmanes-lab/DoveParentsRNAseq
Made with `ggplot`. Played lived on a
keyboard.
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WGCNA identified
96 genes that are
coexpressed with
PRL in the pituitary.
ShinyGO
categorized these
genes by their
Biological Process.
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https://github.com/macmanes-lab/DoveParentsRNAseq
Thanks to Dr. Sarah Davies for the
WGCNA suggestion via Twitter :)
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The top GO terms
are related to the
cell cycle process,
cell proliferation,
reproduction, and
stress response.
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https://github.com/macmanes-lab/DoveParentsRNAseq
Genes identified with WGCNA.
GO terms identified with ShinyGo.
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BRCA1 helps
repair DNA.
Mutations can lead
to increased risk
for breast cancer.
BRCA1 peaks
when PRL peaks
around the time
chicks hatch.
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https://github.com/macmanes-lab/DoveParentsRNAseq
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Understanding the dynamics of PRL
and BRCA1 during avian parental
care could advance cancer
research.
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RNA-seq is not just for
data-driven discovery.
It can be used to test
hypotheses too.
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Hypotheses
Hypothesis 1 (H1)
Changes in transcription
during parental care are
based on an internal
clock-timing mechanism.
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Hypothesis 2 (H2)
Changes in transcription
during parental care are
based on external sensory
information, like the the
presence or absence of
eggs or chicks.
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Egg and chick replacement manipulations.
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https://github.com/macmanes-lab/DoveParentsRNAseq
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When chicks hatch
early, gene
expression is very
similar to incubation
to day 9 and very
different from
normal hatch.
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https://github.com/macmanes-lab/DoveParentsRNAseq
DESeq2: treatment * sex
log fold change
pituitary
H1 H2
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All three
manipulations are
more similar to
their calendar day
equivalent than to
their external
environment.
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https://github.com/macmanes-lab/DoveParentsRNAseq
DESeq2: treatment * sex
log fold change
pituitary
H1 H2 H1
H2 H1
H2
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Egg and chick removal manipulations.
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https://github.com/macmanes-lab/DoveParentsRNAseq
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Offspring removal
manipulations also
suggest that
transcription is
regulated by an
internal clock.
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https://github.com/macmanes-lab/DoveParentsRNAseq
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And prolactin (PRL)
still explains most
of the variation.
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https://github.com/macmanes-lab/DoveParentsRNAseq
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This suggests that pituitary
gene expression is driven by an
internal clock that regulates
prolactin-driven expression of
parental care
behaviors.
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Thanks for listening.
What questions do you have?
Dr. Rayna M. Harris
raynamharris
Postdoc, UC Davis