Isolation and sequence analysis of a cDNA encoding the c subunit of a vacuolar-type H+-ATPase from the CAM plant Kalancho� daigremontiana

Abstract

We report the sequence of a cDNA clone encoding the c ("16 kDa') subunit of a vacuolar-type H(+)-ATPase (V-ATPase) from Kalanchoë daigremontiana, a plant in which the cell vacuole plays a pivotal role in crassulacean acid metabolism. The clone, pKVA211, was isolated from a K. daigremontiana leaf cDNA library constructed in lambda ZAP II using a homologous PCR-generated cDNA probe for the V-ATPase c subunit. The KVA211 cDNA was 839 nucleotides long and included a 20 bp poly(A)+ tail together with a complete 495 bp coding region for a polypeptide with a predicted molecular mass of 16659 Da. The deduced amino acid sequence was highly conserved across the wide range of eukaryotes (vertebrates, invertebrates, fungi, plants and protozoa) in which this gene has now been identified. Sequence comparison of several PCR products and genomic Southern analysis indicated that the V-ATPase c subunit in K. daigremontiana is encoded by a small multi-gene family. Steady-state levels of the KVA211 mRNA were much higher in leaves than in roots or flowers, and expression of this transcript in leaves was shown to be strongly light-dependent.

A COCCOLITHOPHORID CALCIFYING VESICLE WITH A VACUOLAR‐TYPE ATPASE PROTON PUMP: CLONING AND IMMUNOLOCALIZATION OF THE V0 SUBUNIT c

“…vap cDNA encodes 164 amino acids in a polypeptide with a calculated molecular mass of 16,252 Da (Genbank accession number ). The VAP polypeptide showed a high degree of homology to the 16‐kDa, subunit c , V‐type ATP ases of higher plants (Lai et al 1991, Hasenfratz et al 1995, Perera et al 1995, Xiao 1995, Bartholomew et al 1996, Kirsch et al 1996) and a wide range of vertebrate (Birman et al 1990, Hanada et al 1991, Nezu et al 1992), invertebrate (Dow et al 1992), and fungal (Nelson and Nelson 1989, Bowman et al 1992) taxa (Table 1).…”

The photosynthetic plasticity of crassulacean acid metabolism: an evolutionary innovation for sustainable productivity in a changing world

“…, 2002). The final 4‐C product resulting from nocturnal carboxylation is malate, which is transported into the vacuole, where it is accumulated as malic acid as a result of the high concentration of H + generated by the vacuolar H + ‐ATPase and/or H + ‐PPiase (Bartholomew et al. , 1996; Tsiantis et al.…”

Potential of Plants from the Genus Agave as Bioenergy Crops

“…1). The stomata remain closed during the daytime, avoiding the escape of the internally released CO 2 and at the same time preventing the loss of water by transpiration [1,2,35,51].…”