title: A novel heavy metal ATPase peptide from Prosopis juliflora is involved in metal uptake in yeast and tobacco.
abstract: Heavy metal pollution of agricultural soils is one of the most severe ecological problems in the world. Prosopis juliflora, a phreatophytic tree species, grows well in heavy metal laden industrial sites and is known to accumulate heavy metals. Heavy Metal ATPases (HMAs) are ATP driven heavy metal pumps that translocate heavy metals across biological membranes thus helping the plant in heavy metal tolerance and phytoremediation. In the present study we have isolated and characterized a novel 28.9 kDa heavy metal ATPase peptide (PjHMT) from P. juliflora which shows high similarity to the C-terminal region of P1BATPase HMA1. It also shows the absence of the invariant signature sequence DKTGT, and the metal binding CPX motif but the presence of conserved regions like MVGEGINDAPAL (ATP binding consensus sequence), HEGGTLLVCLNS (metal binding domain) and MLTGD, GEGIND and HEGG motifs which play important roles in metal transport or ATP binding. PjHMT, was found to be upregulated under cadmium and zinc stress. Heterologous expression of PjHMT in yeast showed a higher accumulation and tolerance of heavy metals in yeast. Further, transgenic tobacco plants constitutively expressing PjHMT also showed increased accumulation and tolerance to cadmium. Thus, this study suggests that the transport peptide from P. juliflora may have an important role in Cd uptake and thus in phytoremediation.
authors.affiliation: Plant Molecular Biology Lab, M S Swaminathan Research Foundation, 3rd Cross Street, Institutional Area, Taramani, Chennai, Tamil Nadu, 600 113, India.
authors.forename: Nisha S
authors.initials: NS
authors.lastname: Keeran
authors.affiliation: Plant Molecular Biology Lab, M S Swaminathan Research Foundation, 3rd Cross Street, Institutional Area, Taramani, Chennai, Tamil Nadu, 600 113, India.|Department of Genetic Engineering, SRM University, Kattankulathur, Tamil Nadu, 603 203, India.
authors.forename: G
authors.initials: G
authors.lastname: Ganesan
authors.affiliation: Plant Molecular Biology Lab, M S Swaminathan Research Foundation, 3rd Cross Street, Institutional Area, Taramani, Chennai, Tamil Nadu, 600 113, India. ajaykparidamssrf@gmail.com.
authors.forename: Ajay K
authors.initials: AK
authors.lastname: Parida
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics*; D000595:Amino Acid Sequence / Q000235:genetics; D002104:Cadmium / Q000378:metabolism / Q000633:toxicity; D018506:Gene Expression Regulation, Plant; D019216:Metals, Heavy / Q000378:metabolism* / Q000633:toxicity; D010455:Peptides / Q000235:genetics; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development; D029862:Prosopis / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D012987:Soil / Q000737:chemistry; D014026:Nicotiana / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D015032:Zinc / Q000378:metabolism / Q000633:toxicity
chemical_list: D019216:Metals, Heavy; D010455:Peptides; D012987:Soil; D002104:Cadmium; D000251:Adenosine Triphosphatases; D015032:Zinc
keywords: Heavy metal ATPase; Heavy metal tolerance; Heavy metals; Hyperaccumulator; P. juliflora; Phytoremediation