Cell News 01/2017
21
Polarity protein-mediated control of tissue repair
Ali, Noelle JA; Bauer, Ronja; Eming, Sabine; Iden, Sandra
SESSION 1: CELL BIOLOGY BY NUMBERS
Presenting author: Sandra Iden
University of Cologne, Cologne, Germany
Plasticity in cyto-architecture is essential for the homeostasis,
function and repair of tissues. We earlier reported crucial roles
of the Par3-aPKC-Par6 complex in epidermal homeostasis and
different skin malignancies. How polarity proteins contribute
to tissue remodeling following damage, however, is largely un-
known. Mechanical skin injury elicits a wound healing program
to quickly re-establish barrier function and tissue integrity,
though mechanisms determining if wounds heal efficiently
are still poorly understood. Here we assessed a role of Par3 in
skin repair in mice. Epidermal Par3 loss delayed the closure
of full-thickness wounds and led to aberrant ECM-integrin
expression, reduced keratinocyte elongation and organelle
positioning. Low PAR3 expression was associated with human
wound pathologies, i.e. non-healing wounds upon venous in-
sufficiency. Together, these data suggest that Par3 drives tissue
repair through control of intrinsic polarity and cell-matrix
interactions.
Development of a polyclonal antibody for
phosphorylated mannooligosaccharide -
Its potential use in detecting mannose
phosphorylated proteins
Nadimpalli Siva Kumar, Ismail Khan, Ajith Kumar Aravindakshan and Poorna Manasa Bhamidimarri
Presenting author: Nadimpalli Siva Kumar
Glycobiology Laboratory, Department of Biochemistry, School
of Life Sciences, University of Hyderabad, Hyderabad 500046,
Telangana, India
O-Phosphomannan from yeast is a highly complex polysaccha-
ride that is used to generate phosphorylated oligosaccharides.
Acid hydrolysis of the polysaccharide can generate two types
of oligosaccharide a highly branched high molecular weight
phopshomannan core (PMC) and penta mannosyl phosphate
(PMP). Both PMC and PMP have been used as functional
ligands for the affinity purification of mannose 6-phosphate
receptors (Siva Kumar, 1996, Nadimpalli and von Figura 2002).
Antibodies to purified proteins, receptors and lysosomal en-
zymes have been used extensively to understand the functions
of lysosomal enzymes and their sorting receptors MPR300
and MPR46. In an earlier study we also developed an ELISA to
quantify the receptors in different tissues. The common feature
of all lysosomal enzymes is the presence of phosphorylated
oligosaccharide attached to the enzyme which is recognized
by the MPR proteins that facilitates their transport within the
cell or internalization by the MPR300 protein from the cell
surface into the cells. However there has been no report on the
development of an antibody that can recognize the phos-
phorylated mannose residues in lysosomal enzymes. Such an
antibody would have potential applications to detect lysosomal
enzymes using small ample volume. In the present study we
successfully raised a polyclonal antiserum for phosphomannan
core. From the antiserum specific IgG was affinity purified on
phosphomannan core-immobilized to gel. The antibody specif-
ically recognizes not only the phosphomannan core but also
a wide variety of lysosomal enzymes which contain mannose
6-phosphate glycan such as the
α
-mannosidase,
α
-fucosidase,
β
-hexosaminidase in western blot experiments. Furthermore,
the antibody could also recognize mannose 6-phosphate
containing glycoproteins such as the human DNase 1, but not
glycoproteins that lack mannose 6-phosphate. These antibod-
ies would have potential use in detection of lysosomal enzymes
and m6p containing biological molecules.
