Salser SJ et al. (1994) Worm Breeder's Gazette "mab-5 Expression Repeatedly Switches ON and OFF in the V5 Lineage"

Kenyon CJ, Salser SJ

[Worm Breeder's Gazette, 1994]

mab-5 Expression Repeatedly Switches ON and OFF in the V5 Lineage S. Salser and C. Kenvon, UCSF, San Francisco, CA. 94143

Palmer RE et al. (1994) Worm Breeder's Gazette "Use of an Expression Library to Clone Genes by Complementation"

Palmer RE, Sternberg PW

[Worm Breeder's Gazette, 1994]

Use of an expression library to clone genes by complemcntation. RE. Palmer and P.W. Sternberg, HHMI and Division of Biology, Caltech, Pasadena, CA 91125

Simske JS et al. (1994) Worm Breeder's Gazette "Specification of Vulval Cell Fates By Sequential Signalling Pathways."

Simske JS, Kim SK

[Worm Breeder's Gazette, 1994]

Specification of vulval cell fates by sequential signaling pathways Jeffrey S. Simske and Stuart K. Kim, Dept. of Developmental Biology, Stanford University Medical Center, Stanford CA 94305

Sommer RJ et al. (1994) Worm Breeder's Gazette "Evolution of Vulva-Formation: Part II: Species With a Central Vulva"

Sommer RJ, Sternberg PW

[Worm Breeder's Gazette, 1994]

Evolution of vulva-formation: Part II: Species with a central vulva Ralf J. Sommer & Paul W. Sternberg, California Institute of Technology, Division of Biology 156-29, Pasadena, CA 91125

Kenyon CJ et al. (1994) Worm Breeder's Gazette "Activity of the polyray-1 Maintenance Gene Must Be Overcome To Allow For Correct Temporal Expression of HOM-C Genes"

Kenyon CJ, Maloof JN

[Worm Breeder's Gazette, 1994]

Activity of the polyray-1 maintenance gene must be overcome to allow for correct temporal expression of HOM-C genes Julin Maloof and Cynthia Kenyon, Dept of Biochemistry, UCSF, San Francisco, CA 94143 0554

Schachat FH et al. (1981) Worm Breeder's Gazette "characterization and roles of calmodulin and a second calcium regulatory protein from C elegans."

Schachat FH, Vanaman TC, Bronson DD, Jamieson G

[Worm Breeder's Gazette, 1981]

In these studies we have purified and characterized two proteins involved in Ca-regulation in Caenorhabditis st is calmodulin (CaM) which is considered to be an intracellular receptor for calcium because of the large number of cellular processes it activates in a Ca-dependent manner. The second protein which is similar to CaM in many of its physical and chemical properties, we have called the troponin-C like protein (TnCLP) . Because of a report which suggested invertebrate CaMs are dissimilar to those of vertebrates our studies on C. elegans CaM have focused on a comparison of its properties to those of bovine brain CaM. The C. elegans protein shows no major difference in amino acid composition, cyanogen bromide (CNBr) peptide maps, electrophoretic behavior or enzymatic properties in those studies. The C. elegans TnCLP, which copurifies with the CaM until DE-52 ion exchange chromatography, can be distinguished from CaM. It differs in amino acid composition, CNBr peptide maps and molecular weight, and lacks the ability to activate bovine brain cyclic nucleotide phosphodiesterase. Our concern with it has centered about defining its possible physiological roles. TnCLP forms Ca-dependent complexes with rabbit fast skeletal muscle troponin I and troponin T. It copurifies with thin myofilaments. These observations coupled with its inability to activate bovine brain cyclic nucleotide phosphodiesterase suggest that C. elegans TnCLP is not a second generalized Ca-dependent activator like CaM, but functions as a troponin C. We believe that the C. elegans TnCLP and CaM are responsible for the 2 thin and thick myofilament Ca-regulation that has been reported in C. elegans. The TnCLP acting in a troponin-like complex to regulate thin filaments. The CaM acting on thick filaments through a myosin light chain kinase as has been reported for other actomyosin contractile systems. In support of that later contention we have shown that there is an in vitro Ca and CaM dependent phosphorylation of one of the C. elegans myosin light chains. We expect these studies will serve as the basis for elucidating the Ca-dependent events in muscle contraction (as well as in other processes) both in vivo and in vitro through the analysis of genetic variants of C. elegans that may be blocked in different steps or pathways of Ca-regulation.

Sommer RJ et al. (1994) Worm Breeder's Gazette "Evolution of Vulva Formation: Part IV: Variation in AC Position Can Cause a Shift of Vulva Formation Towards P(4-6).p."

Sternberg PW, Sommer RJ

[Worm Breeder's Gazette, 1994]

Evolution of vulva formation: Part IV: Variation in AC position can cause a shift of vulva formation towards p(4- 6).p Ralf J. Sommer & Paul W. Sternberg, HHMI & California Institute of Technology, Division of Biology 156-29, Pasadena, CA

Weisblat D et al. (1975) Worm Breeder's Gazette "Electrophysiological Studies of Ascaris Muscle"

Byerly L, Russell RL, Weisblat D

[Worm Breeder's Gazette, 1975]

Using Ascaris as a model system, we are studying ionic mechanisms of the spontaneous electrical activity in nematode somatic muscle. The fast spike potentials appear to be Ca+2 mediated; their amplitude depends on the external Ca+2 concentration, they are TTX insensitive, they persist when Na+ is replaced by Tris+, choline+, or Cs+, and they are blocked by Co+2 and La+3. When the normal solution is replaced by one containing 11 mM Ba+2 and 0.15 mM Ca+2 as the only divalent cations, the slow waves underlying the normal spike activity appear to increase dramatically in amplitude and duration; spike activity gradually disappears. The duration and amplitude of the slow waves at steady state under these conditions increase with Ba+2 concentration, reaching values of 1-2 minutes and 50-60 mV, respectively, in 26 mM Ba+2. These results and others lead us to conclude that the slow waves are also Ca+2 mediated. The muscles are depolarized by 0.1 mM ouabain, suggesting some involvement of an electrogenic pump in maintaining the membrane potential. TEA, in concentrations as low as 1 mM, has pronounced effects on the spontaneous myogenic activity, consistent with the effects observed when TEA is injected iontophoretically into C. elegans.

Chuang P-T et al. (1994) Worm Breeder's Gazette "DPY-27: A Protein Required For Dosage Compensation is Associated With the X Chromosome in XX Animals"

Chuang P-T, Meyer BJ, Albertson DG

[Worm Breeder's Gazette, 1994]

Dpy-27: A Protein Required for Dosage Compensation Is Associated with the X chromosome in XX Animals Pao-Tien Chuangl, Donna Albertson2 and Barbara Meyerl, Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720~ and MRC Laboratory of Molecular biology, Hills Road, Cambridge, CB2 2QH UK2

Cowden C et al. (1986) Worm Breeder's Gazette "a CCK-like neuropeptide in Ascaris."

Stretton AOW, Cowden C

[Worm Breeder's Gazette, 1986]

Our aim is to obtain peptides of known sequence from Ascaris in order to determine their mode of action using electrophysiological methods. Since McIntire and Horvitz (C. elegans CSH Abstracts 1985) showed that cholecystokinin-like immunoreactivity (CCK-LI) is present in certain neurons in C. elegans, we are initially investigating the role of a CCK-like peptide (CCK-LP) in the nervous system of Ascaris using anti-CCK8 antisera to detect and localize CCK-LI. Using the methods developed by Johnson (see Johnson and Stretton, Soc. Neurosci. Abstr. 9: 302; Sithigorngul, Johnson and Stretton, C. elegans CSH Abstracts 1985) we find that in Ascaris, CCK-LI is concentrated in 2 cells (AVF cells) in the ventral nerve cord, in 3 cells in the ventral ganglion, in 4 processes in the ventral cord, and in 2 processes in the lateral line. Thus the CCK-LP is concentrated in a small minority of the 180 neurons present in the anterior region of adult Ascaris.We have developed a procedure for extracting the CCK- LP from C. elegans and fractionating the extract on a C18 cartridge. High voltage paper electrophoresis shows that added radioiodinated CCK8 is chemically intact after this extraction and after fractionation. The CCK-LP was separated from more hydrophilic components with a 20-40% gradient of acetonitrile on reversed phase HPLC. RIA's detected CCK-LI associated with a peak of optical density. Addition of authentic CCK8 (non-sulfated) to the sample showed that the RIA-positive peak was close to, but distinctly separate from, CCK8. Assuming that the specific immunoreactivity of nematode CCK-LP and mammalian CCK8 is the same, we can obtain 100 pmoles from 60g of C. elegans. From this crude estimate, it seems that the levels of recoverable peptide are sufficient for amino acid sequence determination which is now our top priority.