Serine/threonine-protein kinase which plays a role, during oogenesis, in chromosome pairing and synapsis, by facilitating the recruitment and attachment of meiotic chromosomes to the nuclear envelope during prophase (PubMed:22018922, PubMed:22018921). Promotes the localization of brc-1 to the short arm of homologous chromosomes during meiotic prophase I (PubMed:30383754). Regulates the formation of sun-1 patches along the nuclear envelope (PubMed:22018922, PubMed:22018921). Promotes meiotic nuclei apoptosis in response to chromosomal asynapsis (PubMed:22018922). Plays a redundant role with plk-1 in the establishment of cell polarity downstream of mex-5 and mex-6 during the first embryonic cell divisions (PubMed:18199581). Plays a role in nicotinic acetylcholine receptor-mediated sensitivity to nicotine but not levamisole (PubMed:15990870). Regulates motility (PubMed:15990870). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Interacts (via POLO box domain) with mex-5 and mex-6 (PubMed:18199581, PubMed:22018922). Interacts (via POLO box domain) with him-8 (via N-terminus); the interaction mediates plk-2 recruitment to the pairing region of X chromosomes during meiosis (PubMed:22018922). Interacts with sun-1 (PubMed:22018921). May interact with nicotinic acetylcholine receptor (PubMed:15990870). During meiosis I, localizes to chromosome pairing centers formed at the nuclear envelope in early pachytene and then to the synaptonemal complex in mid and late pachytene (PubMed:22018922, PubMed:22018921). Co-localizes at pairing centers with him-8, zim-3, zyg-12 and sun-1 and partially with plk-1 in early prophase (PubMed:22018922, PubMed:22018921). Co-localizes with syp-1 in synapsed chromosomes at pachytene (PubMed:22018921). Co-localizes with brc-1 in pachytene nuclei (PubMed:30383754). Localizes asymmetrically in the 1-cell embryo which results in higher levels in the somatic cell AB than in the germline blastomere P1 (PubMed:18199581). Expressed in oocytes. Expressed in the early stages of embryogenesis. Mutants are viable and fertile but about 30-percent of the progeny die at the embryonic stage. Surviving adults are mostly male (PubMed:22018922). Impaired chromosome pairing and synapsis during meiotic prophase. Asymmetric disassembly of the synaptonemal complex fails at the diplotene stage. Partial mis-segregation of chromosomes. Increased germline apoptosis (PubMed:22018922). Simultaneous knockdown of plk-1 and plk-2 causes a loss in pie-1 polarization in the 1-cell embryo, an increased association with the oocyte pronuclei and a decrease in pie-1 degradation in embryonic somatic cells (PubMed:18199581). Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. CDC5/Polo subfamily.