Probe:	HtrA1 cDNA1
Probe preparation:	Antisense labelled with digoxigenin RNA
Assay notes:	Another non-overlapping probe (MGI:5565366) gave identical results.

Structure	Level	Pattern	Image	Note
TS20: embryo mesenchyme	Present	Regionally restricted	1A right	Expressed in a pattern closely associated with skeletal elements of the vertebral column and limbs.
TS20: limb mesenchyme	Present		1A right

Structure	Level	Pattern	Image	Note
TS20: rib pre-cartilage condensation	Absent		1D , 1B
TS20: tendon	Present	Regionally restricted	1D , 1B	Expressed along the vertebrae.
TS20: connective tissue	Present	Regionally restricted	1B , 1D	Expressed in the ligaments along the vertebrae.
TS20: body wall mesenchyme	Present	Regionally restricted	1D , 1B	Expressed in the undifferentiated mesenchymal cells surrounding precartilage condensations.
TS20: forebrain	Present	Regionally restricted	1B	Expressed in specific regions of the neuroepithelium in close association with development of the choroid plexus.
TS20: hindbrain	Present	Regionally restricted	1B	Expressed in specific regions of the neuroepithelium in close association with development of the choroid plexus.
TS20: dermis	Present	Regionally restricted	1B	Expressed in the thoraco-abdominal region.
TS20: epidermis	Present	Regionally restricted	1B	Expressed in the thoraco-abdominal region.

Structure	Level	Pattern	Image	Note
TS22: tendon	Present	Regionally restricted	1C	Enhanced expression along the vertebrae.
TS22: connective tissue	Present	Regionally restricted	1C	Enhanced expression in the ligaments along the vertebrae.
TS22: body wall mesenchyme	Present	Regionally restricted	1C	Enhanced expression in the undifferentiated mesenchymal cells surrounding precartilage condensations.
TS22: hindbrain	Present	Regionally restricted	1E , 1C	Expressed in specific regions of the neuroepithelium in close association with development of the choroid plexus.
TS22: choroid plexus	Absent		1E , 1C
TS22: heart valve	Strong		1C
TS22: outflow tract	Strong		1C
TS22: lung mesenchyme	Present	Regionally restricted	1C	Expressed in the mesenchymal cells beneath the lung epithelium.

Structure	Level	Pattern	Image	Note
TS20: atrioventricular endocardial cushion	Present		1G

Structure	Level	Pattern	Image	Note
TS20: nephric duct	Absent		1H
TS20: gonadal mesenchyme	Present		1H
TS20: mesonephric tubule	Present		1H
TS20: paramesonephric duct	Present		1H

Structure	Level	Pattern	Image	Note
TS20: lung mesenchyme	Present	Regionally restricted	1I	Expressed in the mesenchymal cells beneath the lung epithelium.

Structure	Level	Pattern	Image	Note
TS22: vibrissa epidermal component	Present		1J

Structure	Level	Pattern	Image	Note
TS21: forelimb joint	Present		2A

Structure	Level	Pattern	Image	Note
TS21: forelimb joint	Present		2B
TS21: tendon	Present		2B
TS21: connective tissue	Present	Regionally restricted	2B	Expressed in the ligaments that develop from mesenchyme in the vicinity of the precartilage condensations.

Structure	Level	Pattern	Image	Note
TS22: tendon	Present	Regionally restricted	2C	Expressed in the extensor tendon primordium.

Structure	Level	Pattern	Image	Note
TS22: perichondrium	Present		2D
TS22: periosteum	Present		2D
TS22: rib cartilage condensation	Present	Regionally restricted	2D	Expressed in the primary ossification center, not in precartilage condensations and chondrocytes.

Structure	Level	Pattern	Image	Note
TS25: hindlimb tendon	Present		2F , 2F inset
TS25: ligament	Present		2F , 2F inset
TS25: foot joint	Weak		2F , 2F inset	Expressed only in the thin layer of articular surfaces.