Sonic hedgehog protein signals not as a hydrolytic enzyme but as an apparent ligand for Patched

The amino-terminal signaling domain of the Sonic hedgehog secreted protein (Shh-N), which derives from the Shh precursor through an autoprocessing reaction mediated by the carboxyl-terminal domain, executes multiple functions in embryonic tissue patterning, including induction of ventral and suppression of dorsal cell types in the developing neural tube. An apparent catalytic site within Shh-N is suggested by structural homology to a bacterial carboxypeptidase. We demonstrate here that alteration of residues presumed to be critical for a hydrolytic activity does not cause a loss of inductive activity, thus ruling out catalysis by Shh-N as a requirement for signaling. We favor the alternative, that Shh-N functions primarily as a ligand for the putative receptor Patched (Ptc). This possibility is supported by new evidence for direct binding of Shh-N to Ptc and by a strong correlation between the affinity of Ptc-binding and the signaling potency of Shh-N protein variants carrying alterations of conserved residues in a particular region of the protein surface. These results together suggest that direct Shh-N binding to Ptc is a critical event in transduction of the Shh-N signal.

Chicken double-stranded RNA adenosine deaminase has apparent specificity for Z-DNA.

A M(r) 140,000 protein has been purified from chicken lungs to apparent homogeneity. The protein binds with high affinity to a non-BNA conformation, which is most likely to the Z-DNA. The protein also has a binding site for double-stranded RNA (dsRNA). Peptide sequences from this protein show similarity to dsRNA adenosine deaminase, an enzyme that deaminates adenosine in dsRNA to form inosine. Assays for this enzyme confirm that dsRNA adenosine deaminase activity and Z-DNA binding are properties of the same molecule. The coupling of these two activities in a single molecule may indicate a distinctive mechanism of gene regulation that is, in part, dependent on DNA topology. As such, DNA topology, through its effects on the efficiency and extent of RNA editing may be important in the generation of new phenotypes during evolution.

Comparison of ratios of imports to apparent consumption, 1968-72.

At head of title: 93d Congress. 1st session. Committee print.

Studies of the Pre-Buggy II apparent craters /

"Issued: June 1965"--cover.

A discovery of the author of the letters of Junius, founded on such evidence and illustrations as explain all the mysterious circumstances and apparent contradictions which have contributed to the concealment of this "most important secre of our time."

Micro-opaque. Louisville, Ky., Lost Cause Press, 1956? 4 cards. 8 x 13 cm.

Antonii Mizaldi Monsluciani Phaenomena siue disputatio, omnium aeris commotionum signa ab iis quae in coelo, aëre, aqua & terra palam apparent quatuor aphorismorum sectionibus, methodo quam maxime perspicua, diebus singulis fideliter ob oculos ponens, eiusdem prolegomena ...

Mode of access: Internet.

A historical view of the Hindu astronomy, from the earliest dawn of that science in India to the present time. In two parts. Part I. The ancient astronomy. Part II. The modern astronomy, with an explanation of the apparent cause of its introduction, and the various impositions that followed. To which are added, I. Hindu tables of equations. II. Remarks on the Chinese astronomy. III. Translations of certain hieroglyphics, called the Zodiacs of Dendera.

Mode of access: Internet.

The life of Martin Van Buren, heir-apparent to the "government," and the appointed successor of General Andrew Jackson. Containing every authentic particular by which his extraordinary character has been formed. With a concise history of the events that have occasioned his unparalleled elevation; together with a review of his policy as a statesman ...

Also attributed to A.S. Clayton.

The conciliator of R. Manasseh ben Israel : a reconcilement of the apparent contradictions in Holy Scripture /

Includes bibliographical references and index.

Some observations on Socinian arguments : to which are added, some apparent causes of the progress of the Socinian opinions concerning Christ : with a collection of scripture evidence against these opinions /

Mode of access: Internet.

De quatuor signis quae apparent in vnguibus manuum /

Signatures: A-D⁸ E⁴.

Canada; the country, its people, religions, politics, rulers, and its apparent future, being a compendium of travel from the Atlantic to the Pacific, the Great Lakes, Manitoba, the North-West, and British Columbia, with a description of their resources, trade, statistics, together with the legends of the Ottawa, the lower St. Lawrence, and the coast. With 40 illustrations, rapids of the St. Lawrence, &c.

"Copyright Washington, D.C., 1881. Ottawa, 1882. Stationers' Hall, London, Eng., 1882.

The student's assistant in astronomy and astrology : containing observations on the real and apparent motions of the superior planets, the geocentric longitude of the sun and superior planets ... also a discourse on the harmony of phrenology, astrology, and physiognomy /

Mode of access: Internet.

Short, easy, and improved method of finding the apparent time at ship. Rapid calculation of apparent time for finding the longitude.

Mode of access: Internet.

Nonbreeding Eastern Curlews Numenius madagascariensis Do Not Increase the Rate of Intake or Digestive Efficiency before Long-Distance Migration because of an Apparent Digestive Constraint

The possibility of premigratory modulation in gastric digestive performance was investigated in a long-distance migrant, the eastern curlew (Numenius madagascariensis), in eastern Australia. The rate of intake in the curlews was limited by the rate of digestion but not by food availability. It was hypothesized that before migration, eastern curlews would meet the increased energy demand by increasing energy consumption. It was predicted that (1) an increase in the rate of intake and the corresponding rate of gastric throughput would occur or (2) the gastric digestive efficiency would increase between the mid-nonbreeding and premigratory periods. Neither crude intake rate (the rate of intake calculated including inactive pauses; 0.22 g DM [grams dry mass] or 3.09 kJ min(-1)) nor the rate of gastric throughput (0.15 g DM or 2.85 kJ min(-1)) changed over time. Gastric digestive efficiency did not improve between the periods (91%) nor did the estimated overall energy assimilation efficiency (63% and 58%, respectively). It was concluded that the crustacean-dominated diet of the birds is processed at its highest rate and efficiency throughout a season. It appears that without a qualitative shift in diet, no increase in intake rate is possible. Accepting these findings at their face value poses the question of how and over what time period the eastern curlews store the nutrients necessary for the ensuing long, northward nonstop flight.