I agree with Manuel : we need more info.

This process is called endomitosis, if I remember correctly. It can happen in some naturally occuring polyploid cells (human keratinocytes and hepatocytes, plant trichomes,..) , but also probably in mutant or drug-treated cells.

There are some reasons for this phenomenon.

You could check upon the regulators of cytokinesis inside the cell it self.

Others are external factors such as temperature and cytokinesis inhibitors substances. We worked on vincaalkaloid, which positively halt the cytokinesis.

There must be much more things to explore.

Good luck on your research.

Regards.

Sarah Jabari

Defects in spindle attachment and an inactive spindle attahcment checkpoint can cause binucleate cells. Have a look at this paper: http://www.nature.com/nature/journal/v437/n7061/pdf/nature03958.pdf

Thanks Dwi and James !!

I agree with Manuel : we need more info.

This process is called endomitosis, if I remember correctly. It can happen in some naturally occuring polyploid cells (human keratinocytes and hepatocytes, plant trichomes,..) , but also probably in mutant or drug-treated cells.

see

Physiological significance of polyploidization in mammalian cells.

Pandit SK, Westendorp B, de Bruin A.

Trends Cell Biol. 2013 Nov;23(11):556-66. doi: 10.1016/j.tcb.2013.06.002. Epub 2013 Jul 10.

PMID:23849927

Thanks... Didier

Hello Vincent and Manuel, these cells are hepatocytes from a transgenic mouse, which gene I can not tell. Also, these are not treated with any drug. I have been working on hepatocytes from past 3 years and normally I have seen 1-2 nuclei in the hepatocytes and rarely 4 nuclei. The transgene itself is not known yet to show such characteristics in general. This multi-nuclei process, I have never seen before that's why I am excited to find out what could be the potential reasons?? As far as I know endomitosis is he process of chromosome replication without nucleus division which ends up as polyploidy. However, I am observing multiple nuclei.

You may want to look at Babak Nami’s question: "What is this kind of morphology." the occurrence of multinucleated cells in cell culture (by endomitosis or fusion) seems to be an in vitro phenomenon.

If some proteins regulating actin cytoskeleton and membrane traffic fail during cytokinesis, the cleavege furrow also could be lost, generating a stop in cytokinesis, and one cell with two nucleous.

Maybe you could check this paper:

http://www.cell.com/current-biology/retrieve/pii/S0960982211013789

Regards.

Hi Manuel, thanks for your suggestions and inputs. I will definitely read your suggestions.

Perhaps I was not clear about my question. I am aware that 1-2 nuclei, sometimes 4 nuclei and polyploidy are common for hepatocytes which I have been seeing in past years. However, recently in these transgenic hepatocytes, I am seeing more than 4 nuclei ( 6-18 nuclei and even more in some cells). That is my concern.

Your description is very clear. I have seen the same phenomenon with primary hepatocytes from avian embryos. Really huge cells with twenty or more nuclei. We saw that first after treatment with carcinogens and got quite excited. But then we found it in untreated controls as well. Possibly more frequent or earlier after carcinogens, but it was never convincing. We considered that as an in vitro phenomenon with little if any meaning and did not follow up. But it is an impressive sight nonetheless. If you have any idea that this could be of significance don’t get discouraged by our decision not to pursue it.

To quote Schopenhauer: „Die Aufgabe ist nicht, zu sehen, was noch niemand gesehen hat, sondern zu denken, was noch niemand gedacht hat über das, was alle sehen.“ Translation: “Thus, the task is not so much to see what no one yet has seen, but to think what nobody yet has thought about that which everybody sees.”

Thanks Herald for your inputs and encouragement. I am sure this phenomenon is significant in my samples but was not sure of its worthiness. I will definitely pursue it to see if I am seeing same phenomenon in vivo in these mice or not?