A specific fraction of avian oviduct chromosomal proteins can be reannealed to pure avian DNA to reconstitute nativelike specific nuclear binding sites (acceptor sites) for the oviduct progesterone receptor (PR). These specific nuclear binding sites represent the difference between the binding to the reconstituted NAP and that to pure DNA. The specific fraction of chromatin protein which contains the acceptor activity, fraction CP-3, is very tightly bound to hen DNA in a complex termed nucleoacidic protein (NAP). Removal of the CP-3 fraction from NAP results in a loss of specific PR binding sites. Resins containing chromatin adsorbed to hydroxylapatite are used as a rapid method to isolate the CP-3 fraction. Reconstitution of the CP-3 fraction to DNA by the described method involving a regressing gradient of 6-0 M guanidine hydrochloride (Gdn-HCl) results in a reconstituted NAP which displays specific PR binding sites identical with those in native (undissociated) NAP and whole chromatin. Optimal conditions and potential problems for reconstituting these nucleoproteins are described. Only partially purified receptor preparations were used in these cell-free binding analyses since they have been shown to bind with similar properties and patterns as the nuclear binding in vivo. Therefore, the binding of PR to the reconstituted NAPs was demonstrated to be receptor dependent, saturable, and of high affinity. Further, the pattern of binding to the reconstituted sites mimics those which are observed in vivo. Thus, nonfunctional receptors that cannot translocate and bind to the nuclear acceptor sites in vivo also failed to bind to the acceptor sites on the reconstituted NAPs generated by the acceptor proteins. In contrast, the binding to pure DNA does not reflect these receptor differences in receptor bindings. Specific binding of PR to reconstituted NAP can be reversed by again removing the protein fraction. Moreover, the specific binding can be destroyed by proteases and protected by protease inhibitors, indicating that acceptor activity is proteinaceous in nature. The reconstitution of the activity is both a concentration-dependent and time-dependent process. During the reconstitution, acceptor activity appears to reconstitute on the DNA when the Gdn-HCl concentration reaches 2.0 M. By use of the reconstitution method as an assay for acceptor activity, the activity in the CP-3 fraction was shown by molecular sieve chromatography to elute in a relatively broad molecular weight range between 13 000 and 25 000. The activity also focuses in isoelectric focusing resins with apparent pI's of 5.2 and 6.4.(ABSTRACT TRUNCATED AT 400 WORDS)
The specific, high-affinity binding of the avian oviduct progesterone receptor (PR) with target-cell nuclei and chromatin has been shown to involve DNA complexed with specific chromatin acceptor proteins. One of these chromatin acceptor proteins has been partially purified and found to be a small hydrophobic protein with a broad pI of 5.0-6.0 [Goldberger, A., & Spelsberg, T. C., (1988) Biochemistry 27, 2103-2109]. This paper describes the final purification over 100,000-fold to apparent homogeneity of this candidate PR acceptor protein, termed the receptor binding factor 1 (RBF-1). When the avian genomic DNA is bound by RBF-1, saturable, high-affinity (KD approximately 2 x 10(-9) M) binding sites for PR are generated. RBF-1 has a unique, hydrophobic N-terminal sequence. The PR binding to the RBF-1-DNA complexes is shown to be dependent on an intact activated PR with which excess nonradiolabeled PR can compete. By use of a new, highly specific monoclonal antibody (mAb) to the RBF-1 with Western immunoblotting, RBF-1 was shown to be localized in the nucleus and to be tissue and species specific. Selective removal of the chromatin proteins containing RBF-1 results in the loss of the highest affinity class of PR binding sites. A second class of residual PR binding sites remains in the nucleoacidic protein (NAP), a complex of proteins more tightly bound to the DNA. This class of PR binding activity has been classified as the RBF-2. The RBF-1 is estimated to be 0.03% of the total chromatin protein with about 1.2 x 10(5) molecules/diploid cell.
The specific high affinity binding of the avian oviduct progesterone receptor (PR) to target cell nuclei and chromatin has been shown to involve DNA complexed with specific chromatin acceptor proteins. One of these chromatin acceptor proteins has been partially purified and found to be a small hydrophobic protein with a broad pI of 5.0-6.0 [Goldberger and Spelsberg (1988), Biochem. 27, 2103-2109]. Using western immunoblots with anti-RBF-1 polyclonal antibodies to monitor the purification, a 10 kD candidate acceptor protein, termed the Receptor Binding Factor-1 (RBF-1), has been purified to apparent homogeneity. RBF-1 has an amino acid composition consistent with a hydrophobic protein having an acidic pI and a unique N-terminal sequence. Two-dimensional polyacrylamide gel electrophoresis and high-performance capillary electrophoresis support the purity of a protein congruent to 10 kD in size, having an acidic pI, but with evidence of several differently charged isoforms. Phosphatase treatment provides evidence that charge heterogeneity may result from variable phosphorylation states. A role of this factor as a candidate "acceptor protein" in the chromatin acceptor sites for the avian oviduct PR is proposed.
Background: Vasovagal responses associated with acupuncture therapy are relatively uncommon adverse events, occurring in *0.02%-7% of treatments. The complex neurocardiovascular reflexes involved in vasovagal responses can induce a range of symptoms such as dizziness, nausea, sweating, bradycardia, hypotension, and, in some cases, syncope or convulsions. Although patients typically recover quickly with proper support, these events may be of concern and anxiety-producing for both patient and provider. Providers need to be well-versed in methods for prevention and treatment of acupuncture-associated vasovagal responses to promote safe practice environments, patient satisfaction and comfort, and cost-effectiveness. Objectives: To examine the biomedical and Traditional Chinese Medicine mechanisms of vasovagal responses, propose updated terminology, and outline steps for prevention and treatment. Methods: During an 18-month period, 281 community-style acupuncture treatments were performed on family members of admitted patients and hospital staff members at the University of Minnesota Masonic Children's Hospital. Five (1.8%) treatments resulted in documented acupuncture-associated vasovagal response (AAVR) symptoms. Results: All 5 patients recovered from their AAVR symptoms after treatment interventions. After recovery, 3 patients reported reductions in their main complaint symptoms; main complaint symptom outcomes were not recorded for the other 2 patients. Conclusions: As integrative practices become more prevalent in academic institutions and primary care environments, clear communication about, as well as prevention treatment, documentation and reporting of acupuncture-associated adverse events will become increasingly valuable. The authors recommend that clinicians in integrative practice clinical environments consider developing formal AAVR response plans as well as training students, supervising and attending providers, and ancillary staff members to ensure rapid, prepared handling and documentation of AAVR incidents.
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