Rare Diseases Symptoms Automatic Extraction
Home
A random Abstract
Our Project
Our Team
oca2 Regulation of chromatophore differentiation and number is cell type specific in zebrafish.
[oculocutaneous albinism]
We
characterized
a
zebrafish
mutant
that
displays
defects
in
melanin
synthesis
and
in
the
differentiation
of
melanophores
and
iridophores
of
the
skin
and
retinal
pigment
epithelium
.
Positional
cloning
and
candidate
gene
sequencing
link
this
mutation
to
a
410
-
kb
region
on
chromosome
6
,
containing
the
oculocutaneous
albinism
2
(
oca
2
)
gene
.
Quantification
of
oca
2
mutant
melanophores
shows
a
reduction
in
the
number
of
differentiated
melanophores
compared
with
wildtype
siblings
.
Consistent
with
the
analysis
of
mouse
Oca
2
-
deficient
melanocytes
,
zebrafish
mutant
melanophores
have
immature
melanosomes
which
are
partially
rescued
following
treatment
with
vacuolar-
type
ATPase
inhibitor
/
cytoplasmic
pH
modifier
,
bafilomycin
A
1
.
Melanophore-
specific
gene
expression
is
detected
at
the
correct
time
and
in
anticipated
locations
.
While
oca
2
zebrafish
display
unpigmented
gaps
on
the
head
region
of
mutants
3
days
post-fertilization
,
melanoblast
quantification
indicates
that
oca
2
mutants
have
the
correct
number
of
melanoblasts
,
suggesting
a
differentiation
defect
explains
the
reduced
melanophore
number
.
Unlike
melanophores
,
which
are
reduced
in
number
in
oca
2
mutants
,
differentiated
iridophores
are
present
at
significantly
higher
numbers
.
These
data
suggest
distinct
mechanisms
for
oca
2
in
establishing
differentiated
chromatophore
number
in
developing
zebrafish
.
