Results: 4

1.
FIG. 2.

FIG. 2. From: Targeted Disruption of the Mouse Mel1b Melatonin Receptor.

The mouse Mel1b receptor sequence. The sequence of the mouse Mel1b receptor has been aligned with other members of the melatonin receptor gene family: mouse Mel1b (present work), human Mel1b (30), mouse Mel1a (34) (NP_032665), and human Mel1a receptor (29) (NP_005949). Putative transmembrane domains are indicated by underlining in the sequence for the mouse Mel1b receptor. Gaps introduced to optimize alignment are indicated by dashes. Consensus sequence is defined as residues that are identical in all four of the sequences shown.

Xiaowei Jin, et al. Mol Cell Biol. 2003 February;23(3):1054-1060.
2.
FIG. 3.

FIG. 3. From: Targeted Disruption of the Mouse Mel1b Melatonin Receptor.

Inhibition of SCN multiunit activity by melatonin. Inhibition of SCN electrical activity by melatonin (0.1 to 100 nM) was assessed during midday. Data are plotted as the percent inhibition of electrical activity observed at the 100 nM dose relative to the level of electrical activity from the same slice exposed to vehicle. The left set of bars shows that the inhibition of SCN electrical activity is absent in Mel1a receptor-deficient (−/−) mice (data replotted from reference 23; sample sizes 7 to 11 per group). Right bars show inhibition of SCN activity in experiments conducted for this study, using Mel1b receptor-deficient mice (−/−) (n = 6) and wild-type control (+/+) (n = 11) mice. The inhibition of electrical activity in each group was significant (P < 0.0001, one-sample t tests, versus 0% inhibition), and there was no significant difference between the Mel1b −/− and Mel1b +/+ groups (t test, P = 0.2).

Xiaowei Jin, et al. Mol Cell Biol. 2003 February;23(3):1054-1060.
3.
FIG. 4.

FIG. 4. From: Targeted Disruption of the Mouse Mel1b Melatonin Receptor.

Inhibition of CREB phosphorylation levels by melatonin. Semiquantitative densitometric analysis shows that melatonin reduces the number of pCREB-immunoreactive nuclei in PACAP-treated SCN slices. Values represent labeled nuclei per unilateral SCN and are the mean ± SEM for four to five animals per group. In wild-type mice, melatonin (1 nM) reduces PACAP-induced CREB phosphorylation by >70% (41). In contrast, a 1 nM concentration had no significant effect on mice with targeted disruption of the Mel1a melatonin receptor (Mel1a −/−) (A). At higher melatonin concentrations (100 nM), a more complete suppression occurs even in mice with disruption of the Mel1a receptor subtype (A) (far right). This residual, higher-threshold response is absent in mice with targeted disruption of both the Mel1a and Mel1b receptors (B). +++, significant difference between vehicle control and PACAP treatment (P < 0.002, t test); ∗∗, significant difference versus PACAP group (P < 0.01, Dunnett's test); NS, not significantly different from PACAP group (P > 0.05, Dunnett's test).

Xiaowei Jin, et al. Mol Cell Biol. 2003 February;23(3):1054-1060.
4.
FIG. 1.

FIG. 1. From: Targeted Disruption of the Mouse Mel1b Melatonin Receptor.

Mel1b receptor gene, targeting construct, and genotyping strategies. (A) Schematic of the Mel1b receptor gene and the targeting construct. A neomycin resistance gene driven by the phosphoglycerate kinase promoter (PGK-Neo cassette) was inserted in reverse orientation at the SmaI site within exon 1 of the mouse Mel1b receptor gene. The 5′ and 3′ arms of the targeting construct were 2.2 and 7 kb, respectively. (B) Genotyping by Southern blot. A BamHI restriction site introduced with the PGK-Neo cassette formed the basis for genotyping by Southern blotting, using a probe (solid bar in panel A) located outside the 5′ end of the construct. Following digestion with BamHI, the probe hybridizes to a ca. 10-kb band in wild-type DNA and a ca. 7-kb band for the targeted allele. Genotypes are shown above the lanes. Lanes illustrate the hybridization pattern of wild-type (W), heterozygous mutant (H), and homozygous Mel1b-receptor mutant (knockout [K]) mice. Approximate sizes of the genomic fragments are indicated at the left. (C) Strategy for genotyping by PCR. Magnified view of the relationship of the primers (arrows) to the nucleotide sequences of the Mel1b receptor gene and the PGK-Neo cassette. (D) Genotyping by PCR. Amplification of mouse genomic DNA with a cocktail of three primers led to amplification of distinct bands representing the wild-type and targeted alleles. Genotypes are shown above the lanes; designations are as in panel B. Size markers on the left indicate bands at 910, 540, 426, 409, 266, and 166 bp, generated by pUC19 and digested with DdeI.

Xiaowei Jin, et al. Mol Cell Biol. 2003 February;23(3):1054-1060.

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Write to the Help Desk