Hedgehog-GLI signaling in positive stromal cells promotes murine nephrogenesis via TGFβ signaling.

Normal kidney function depends on the proper development of the nephron: the functional unit of the kidney. Reciprocal signaling interactions between the stroma and nephron progenitor compartment have been proposed to control nephron development. Here, we show that removal of hedgehog intracellular effector smoothened (-deficient mutants) in the cortical stroma results in an abnormal renal capsule, and an expanded nephron progenitor domain with an accompanying decrease in nephron number via a block in epithelialization.

Activated Hedgehog-GLI Signaling Causes Congenital Ureteropelvic Junction Obstruction.

Intrinsic ureteropelvic junction obstruction is the most common cause of congenital hydronephrosis, yet the underlying pathogenesis is undefined. Hedgehog proteins control morphogenesis by promoting GLI-dependent transcriptional activation and inhibiting the formation of the GLI3 transcriptional repressor. Hedgehog regulates differentiation and proliferation of ureteric smooth muscle progenitor cells during murine kidney-ureter development.

Origin and Function of the Renal Stroma in Health and Disease.

The renal stroma is defined as a heterogeneous population of cells that serve both as a supportive framework and as a source of specialized cells in the renal capsule, glomerulus, vasculature, and interstitium. In this chapter, we review published evidence defining what, where, and why stromal cells are important. We describe the functions of the renal stroma andhow stromal derivatives are crucial for normal kidney function.

Communication: Spectroscopic observation of the O-bonded T-shaped isomer of the CO-CO2 dimer and two of its intermolecular frequencies.

Infrared spectra in the carbon monoxide CO stretch region (≈2150 cm(-1)) are assigned to the previously unobserved O-bonded form of the CO2-CO dimer ("isomer 2"), which has a planar T-shaped structure like that of the previously observed C-bonded form ("isomer 1"), but with the CO rotated by 180°. The effective center of mass intermolecular distances are 3.58 Å for isomer 2 as compared to 3.

Communication: Spectroscopic evidence for a planar cyclic CO trimer.

A high-resolution spectrum in the region of 2144 cm(-1) is assigned to the previously elusive CO trimer. In spite of interference from the CO dimer and some remaining unexplained details, there is strong evidence for a planar, cyclic, C-bonded trimer structure, with C(3h) symmetry and 4.42 Å intermolecular separation, in agreement with theoretical calculations.

CO dimer: the infrared spectrum revisited.

A broad-band (2135-2200 cm(-1)) infrared spectrum of the CO dimer is recorded using a tunable quantum cascade laser to probe a supersonic jet expansion with an effective rotational temperature of about 2.5 K. Analysis of the spectrum reveals the first known levels of the excited state (vCO = 1) with A(+) symmetry and establishes that resonant vibrational splittings are small (<0.