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The autophagy pathway is critical
for homeostasis, cell survival,
cytoprotection, and regeneration.
Evidence exists for transcriptional
regulation of autophagy in the first
few hours following stress or starvation.
We hypothesize that composition,
number and position of multiple
TFBS are organized into distinctive
clusters conserved among functionally
related human autophagy gene promoter
sequences. ATG3, ATG4A, ATG5, ATG4B,
ATG7, MAP1LC3A, ATG9B, ATG10, ATG16l1,
and ATG16l2 promoters were analyzed
with pattern detection and pattern
matching algorithms. Comparisons
of composition, number, and position
of predicted TFBS within conserved
regions in aligned human autophagy
gene promoters identified distinctive
patterns of TFBS clusters. Each
gene's upstream 2kb flanking sequence
contained 129 to 600 TFBS of which
5-30 were conserved among subsets
of autophagy genes. SP1, c/EBP alpha,
and NF1 binding sites were most
abundant. Distinctive clusters identified
were found to be shared by several
autophagy gene promoters. In some
cases, multiple instances of a cluster
were present in a single gene.Clusters
differed among subsets of autophagy
genes, suggesting differential regulation
of autophagy pathway components.
Functional annotation of candidate
transcription factors allows us
to predict regulatory pathways and
physiological stimuli that affect
autophagy gene transcription. This
multi-algorithm a priori analysis
approach together with experimental
confirmation can inform gene expression
and systems biology studies of autophagy.
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