Mapping of the human gene for a melanocyte protein Pmel 17 (D12S53E) to chromosome 12q13-q14

Cyclic siloxane biosurfactant-producing Bacillus cereus BS14 biocontrols charcoal rot pathogen Macrophomina phaseolina and induces growth promotion in Vigna mungo L

Rhizobacteria are vital component of soil-plant interfaces which helps in plant growth responses and disease management. Precisely, the role of biosurfactant production by rhizobacteria in biocontrol mechanisms is underscored. The current study explores the destructive effect of a biosurfactant-producing bacterium Bacillus cereus BS14 on fungal growth under in vitro experiments and showed in vivo reduction of disease severity in pulse crop Vigna mungo. In this study, B. cereus BS14 was observed as plant growth-promoting rhizobacterium (PGPR) based on abilities of production of phytohormone and HCN, phosphate solubilization and biocontrol of Macrophomina phaseolina. The purified biosurfactant from BS14 inhibited the fungal growth by arresting radially growing mycelia. Scanning electron microscope (SEM) study revealed deformities at cellular level in the mycelia of M. phaseolina. The biosurfactant of Bacillus BS14 was identified as cyclic siloxane in GC-MS spectroscopy and FT-IR spectroscopy analyses. In the pot trial studies, B. cereus BS14 proved its efficiency for the growth promotion of Vigna mungo and significantly reduced disease severity index. The present study concludes that biosurfactant of rhizobacterial origin and rhizobacteria can serve for biological control, improvement in crop production and agricultural sustainability. In future, it can be developed as biological control and biofertilizer formulations for legume crops, and commercialized for routine farming practices.

Estrogen receptor β and its domains interact with casein kinase 2, phosphokinase C, and N-myristoylation sites of mitochondrial and nuclear proteins in mouse brain

The localization of estrogen receptor (ER)β in mitochondria suggests ERβ-dependent regulation of genes, which is poorly understood. Here, we analyzed the ERβ interacting mitochondrial as well as nuclear proteins in mouse brain using pull-down assay and matrix-assisted laser desorption ionization mass spectroscopy (MALDI-MS). In the case of mitochondria, ERβ interacted with six proteins of 35-152 kDa, its transactivation domain (TAD) interacted with four proteins of 37-172 kDa, and ligand binding domain (LBD) interacted with six proteins of 37-161 kDa. On the other hand, in nuclei, ERβ interacted with seven proteins of 30-203 kDa, TAD with ten proteins of 31-160 kDa, and LBD with fourteen proteins of 42-179 kDa. For further identification, these proteins were cleaved by trypsin into peptides and analyzed by MALDI-MS using mascot search engine, immunoprecipitation, immunoblotting, and far-Western blotting. To find the consensus binding motifs in interacting proteins, their unique tryptic peptides were analyzed by the motif scan software. All the interacting proteins were found to contain casein kinase (CK) 2, phosphokinase (PK)C phosphorylation, and N-myristoylation sites. These were further confirmed by peptide pull-down assays using specific mutations in the interacting sites. Thus, the present findings provide evidence for the interaction of ERβ with specific mitochondrial and nuclear proteins through consensus CK2, PKC phosphorylation, and N-myristoylation sites, and may represent an essential step toward designing selective ER modulators for regulating estrogen-mediated signaling.

The Silver locus product Pmel17/gp100/Silv/ME20: controversial in name and in function

Mouse coat color mutants have led to the identification of more than 120 genes that encode proteins involved in all aspects of pigmentation, from the regulation of melanocyte development and differentiation to the transcriptional activation of pigment genes, from the enzymatic formation of pigment to the control of melanosome biogenesis and movement [Bennett and Lamoreux (2003) Pigment Cell Res. 16, 333]. One of the more perplexing of the identified mouse pigment genes is encoded at the Silver locus, first identified by Dunn and Thigpen [(1930) J. Heredity 21, 495] as responsible for a recessive coat color dilution that worsened with age on black backgrounds. The product of the Silver gene has since been discovered numerous times in different contexts, including the initial search for the tyrosinase gene, the characterization of major melanosome constituents in various species, and the identification of tumor-associated antigens from melanoma patients. Each discoverer provided a distinct name: Pmel17, gp100, gp95, gp85, ME20, RPE1, SILV and MMP115 among others. Although all its functions are unlikely to have yet been fully described, the protein clearly plays a central role in the biogenesis of the early stages of the pigment organelle, the melanosome, in birds, and mammals. As such, we will refer to the protein in this review simply as pre-melanosomal protein (Pmel). This review will summarize the structural and functional aspects of Pmel and its role in melanosome biogenesis.

Genomic organization and FISH mapping of human Pmel 17, the putative silver locus

The Pmel 17 gene is expressed preferentially in pigment cells. It has been mapped to human chromosome 12 pter-q21 and mouse chromosome 10, near the silver locus. The Pmel 17 gene contains an insertional mutation at its carboxyl terminus in the silver mouse, suggesting that the silver locus might correspond to the gene. In the current studies, we have isolated and characterized human Pmel 17 genomic clones and employed FISH mapping for a precise localization of this gene in the human chromosome. The FISH mapping placed the Pmel 17 gene at human chromosome 12 q12-q13. The human gene consists of nine exons and eight introns, and the entire coding region of the gene spans approximately 7.9 kb of the human chromosome 12. The putative functional domains, such as the signal sequence, histidine-rich, 26-amino acid repeats, cysteinerich, transmembrane and cytoplasmic domains, were encoded by separate exons. Cistranscription elements such as a TATA, a CAT and other potential elements for pigment cell-specific gene expression were found within 1100 base pairs of the 5' flanking region.

Genomic organization and sequence of D12S53E (Pmel 17), the human homologue of the mouse silver (si) locus

We have determined the DNA sequence and genomic organization of D12S53E (Pmel 17), the human homologue of the mouse silver (si) locus. D12S53E encodes a melanosomal matrix protein whose expression is closely correlated with cellular melanin content and which is a frequent melanoma tumor antigen recognized by cytotoxic T lymphocytes. D12S53E is a likely candidate gene for some cases of human oculocutaneous albinism not associated with known albinism loci.