Disease relevance of png

• Ovarian death and sterility result from gnu gain of function. gnu function requires the activity of pan gu and plu [1].

High impact information on png

• We describe genetic interactions among png, plu, and the previously identified gene gnu that demonstrate these three genes regulate the same process [2].
• The phenotype of two png alleles suggests that this gene also may play a direct role in coupling S phase and mitosis during the early cleavage divisions [2].
• The Drosophila plutonium and pan gu genes regulate entry into S phase at fertilization [2].
• Mutations in any of these genes result in unregulated DNA replication and a lack of mitosis ("giant nuclei" phenotype). png encodes a serine/threonine protein kinase, and plu and gnu encode small, novel proteins [3].
• At the transition from meiosis to cleavage mitoses, Drosophila requires the cell cycle regulators encoded by the genes, giant nuclei (gnu), plutonium (plu) and pan gu (png) [1].

Biological context of png

• We have identified the png gene and shown that it encodes a Ser/Thr protein kinase expressed only in ovaries and early embryos, and that the predicted extent of kinase activity in png mutants inversely correlates with the severity of the mutant phenotypes [4].
• We show that PNG, PLU, and GNU constitute a novel protein kinase complex that specifically regulates S-M cell cycles [3].
• Artificial dimerization of PLU via fusion to either GST or FK506 binding protein (in the presence of dimerizing agent) abrogates the requirement for GNU to activate PNG kinase [3].
• Fertilized eggs from plu or png mutant mothers also have a mutant phenotype; DNA replication is uncoupled from nuclear division, resulting in giant, polyploid nuclei [2].

Anatomical context of png

• Mutations in the Drosophila maternal genes plutonium (plu) and pan gu (png) have the striking phenotype that DNA replication initiates in unfertilized eggs [2].

Associations of png with chemical compounds

• In Drosophila, this replication block requires the products of the pan gu (png), plutonium (plu) and giant nuclei (gnu) genes [4].
• Three genes, pan gu (png), plutonium (plu), and giant nuclei (gnu) are required to control the cell cycle specifically at the onset of Drosophila development by inhibiting DNA replication and promoting mitosis [5].

Physical interactions of png

• PNG is a protein kinase that is in a complex with PLU [5].

Regulatory relationships of png

• Mutations in eIF-5A and PP1 87B dominantly suppress png [5].

Other interactions of png

• Ablation of one identified substrate, Mat89Bb, by RNAi produces a polyploid phenotype similar to that of pan gu mutants [6].

References