Planta 235: 137-151 (2012)

Dose- and tissue-specific interaction of monoterpenes with the gibberellin-mediated release of potato tuber bud dormancy, sprout growth and induction of α-amylases and β-amylases

Fig. 4   Molecular phylogenetic analysis of the potato α-amylase gene family reveals clustering into two distinct groups: α-AMY1 and α-AMY2.

(a) The members of the two potato α-amylase groups α-AMY1 and α-AMY2 (phylogenetic tree on the left) differ among each other as presented for the pairwise comparison (table on the right) of their protein sequence identities and pI values (in brackets behind the names). Note that based on these values the α-AMY2 group contains highly conserved members as based on the sequence identities of the 'high-pI' proteins.

(b) Alignment of deduced a-amylase amino acid sequences and characteristic domains as defined by InterPro database. 'M' and the arrow designate a conserved methionine in α-AMY1- and α-AMY2-proteins, which for the α-AMY1-proteins is the N-terminus.

(c) Alignment of α-amylase cDNA sequences and the deduced open reading frames (long arrows). The positions for the group-specific primers for the semi-quantitative RT-PCR are indicated as triangles. Note that the forward primer for the α-AMY2-group is located within the coding sequence while for the α-AMY1-group it is located in a conserved region of the 5' untranslated cDNA region; the small arrow indicates the position of the encoded conserved methionine and the ca. 100-bp sequence downstream of the arrow does not allow the design of a forward primer that distinguishes between the two α-amylase groups.

Accession numbers to GenBank for the potato α-amylases: StAMY1a1 (JK036076), Amy21 (M81682, identical with A21345), StAMY2a1 (JK036077), Amy23 (M79328, identical with A21341), amyA2 (GU134783), amyA1 (GQ406048, identical with A21343 and with MICRO.10377.C2 of Hartmann et al., 2011).