With no explanation, label each line with "O", "other-biologything", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
This
methylation
causes
other
factors
like
histone
deacetylases
(
HDACs
)
to
bind
to
the
chromosome
and
propagate
heterochromatin
formation
,
even
into
active
gene
regions
.
This:O
methylation:O
causes:O
other:O
factors:O
like:O
histone:other-biologything
deacetylases:other-biologything
(:O
HDACs:other-biologything
):O
to:O
bind:O
to:O
the:O
chromosome:O
and:O
propagate:O
heterochromatin:O
formation:O
,:O
even:O
into:O
active:O
gene:O
regions:O
.:O