APL-1, a Caenorhabditis elegans protein related to the human beta-amyloid precursor protein, is essential for viability.
Dominant mutations in the amyloid precursor protein (APP) gene are associated with rare cases of familial Alzheimer's disease; however, the normal functions of APP and related proteins remain unclear. The nematode Caenorhabditis elegans has a single APP-related gene, apl-1, that is expressed in multiple tissues. Loss of apl-1 disrupts several developmental processes, including molting and morphogenesis, and results in larval lethality. The apl-1 lethality can be rescued by neuronal expression of the extracellular domain of APL-1. These data highlight the importance of the extracellular domain of an APP family member and suggest that APL-1 acts noncell-autonomously during development. Overexpression of APL-1 also causes several defects, including a high level of larval lethality. Decreased activity of sel-12, a C. elegans homologue of the human gamma-secretase component presenilin 1, partially rescues the lethality associated with APL-1 overexpression, suggesting that SEL-12 activity regulates APL-1 activity either directly or indirectly.
Hornsten
Angela
A
Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, MA 02215, USA.
Lieberthal
Jason
J
Fadia
Shruti
S
Malins
Richard
R
Ha
Lawrence
L
Xu
Xiaomeng
X
Daigle
Isabelle
I
Markowitz
Mindy
M
O'Connor
Gregory
G
Plasterk
Ronald
R
Li
Chris
C
D016564:Amyloid beta-Protein Precursor / Q000235:genetics*; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology*; D006801:Humans; D007814:Larva / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D018978:Molting / Q000235:genetics
C084891:APL-1 protein, C elegans; D016564:Amyloid beta-Protein Precursor; D029742:Caenorhabditis elegans Proteins; D008565:Membrane Proteins