IIB   20738
INSTITUTO DE INVESTIGACIONES BIOLOGICAS
Unidad Ejecutora - UE
artículos
Título:
A novel GRAIL E3 ubiquitin ligase promotes environmental salinity tolerance in euryhaline tilapia
Autor/es:
DIEGO F. FIOL, ENIO SANMARTI, ANDREANA H. LIM AND DIETMAR KÜLTZ
Revista:
BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2011 vol. 1810 p. 439 - 445
ISSN:
0304-4165
Resumen:
Abstract
Background
Tilapia (Oreochromis mossambicus)
are euryhaline fishes capable of tolerating large salinity changes. In a
previous study aimed to identify genes involved in osmotolerance, we
isolated an mRNA sequence with similarity to GRAIL (Gene Related to
Anergy In Lymphocytes), which is a critical regulator of adaptive
immunity and development. Tilapia GRAIL contains a PA (protease
associated) domain and a C3H2C3 RING finger domain indicative of E3
ubiquitin ligase activity.
Scope of review
Western
blots analysis was used to assess GRAIL expression pattern and
responses to hyperosmotic stress. Immunohistochemistry was used to
reveal the cellular localization of GRAIL in gill epithelium.
Overexpression in HEK293 T-Rex cells was used to functionally
characterize tilapia GRAIL. Salinity stress causes strong up-regulation
of both mRNA and protein levels of tilapia GRAIL in gill epithelium.
Tissue distribution of GRAIL protein is mainly confined to gill
epithelium, which is the primary tissue responsible for osmoregulation
of teleost fishes. Overexpression of tilapia GRAIL in HEK293 cells
increases cell survival (cell viability) while decreases apoptosis
during salinity challenge.
Major conclusions
Our
data indicate that tilapia GRAIL is a novel E3 ubiquitin ligase
involved in osmotic stress signaling, which promotes environmental
salinity tolerance by supporting gill cell function during hyperosmotic
stress.
General significance
Involvement
of tilapia GRAIL in the osmotic stress response suggests that GRAIL E3
ubiquitin ligases play a broader role in environmental stress responses,
beyond their documented functions in adaptive immunity and development.