A Comparison of the Relative Actin Levels in Various Organs in Danio rerio Embryos

Mari Ann Elise SpringerMichael Raymond BukszarElizabeth Rae Kellom

Introduction

Essential for cell movement

Dynamic Monomers vs.

filaments Found in all cells

but especially crucial in muscle

Actin

Organs of Focus Skeletal Muscle Heart Brain

Introduction

48hr

Striated vs. Cardiac Muscle

Introduction

Hypothesis Actin levels in the organs of zebrafish

embryos are differentiated based on muscle density showing actin levels being highest in skeletal muscle, moderate in the heart, and lowest in areas with minimal muscle such as the brain.

Techniques Rhodamine Phalloidin staining

Permeabilization

Methods

Methods (Halpern & Gamse, 2009)

10 3-day-old zebrafish embryos fixed in 4% formaldehyde Washed in PBS + .1% Tween Permeabilized in PBS + 2%Triton for 2 hours Washed in PBS tween Incubated with phalloidin for staining; kept in dark from this

point onward Washed in PBS tween Glycerol Transfer series: 25%, 50%, 80% Embryos were examined and photographed under a fluorescent

microscope; 50 millisecond exposure time Ear and eye analyzed instead of brain Pictures were analyzed for relative actin levels using ImageJ

and compared them using One Way ANOVA

Methods

Results

Heart

Otic Vesicle

Skeletal Muscle

Eye

Figure 1. Relative actin levels in respective Danio riero organs

Otic Vesicle Heart Skeletal Muscle Eye0

0.2

0.4

0.6

0.8

1

1.2

Zebrafish Organ

Rel

ativ

e A

mou

nt o

f A

ctin

Results

Figure 2. One-way ANOVA of actin levels between organs in Danio riero

Otic Vesicle

Heart Skeletal Muscle

Eye

Otic VesicleHeart .753Skeletal Muscle

.289 .791

Eye .002 .001 <.001

Results

Relation to Hypothesis Hypothesis changed slightly during the

experiment

Results did not support hypothesis Few suitable fish for observation & analysis

Discussion

Dynamic HypothesisDiscussion

2-day:

5-day:

Reasoning Extraocular muscles are small & deep Actin is important in ear (Stereocilliary

bundles)

Discussion

Future Research Confocal Microscopy

Smooth vs. skeletal & cardiac muscle

Discussion

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Halpern, M., & Gamse J. Department of Biology (2009, Summer). MBL Embryology. Berkeley: University of California Berkeley.

Kague, E. et al. (2010). Functionally Conserved Cis-Regulatory Elements of COL18A1 identified through zebrafish transgenesis. Developmental Biology, 337: 496-505

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Zhong, T. (2005). Zebrafish Genetics and Formation of Embryonic Vasculature. Current Topics in Developmental Biology, 71: 53-81

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