Precise control of microtubule disassembly in living cells

Microtubules tightly regulate various cellular activities. Our understanding of microtubules is largely based on experiments using microtubule‐targeting agents, which, however, are insufficient to dissect the dynamic mechanisms of specific microtubule populations, due to their slow effects on the entire pool of microtubules. To overcome this technological limitation, we have used chemo and optogenetics to disassemble specific microtubule subtypes, including tyrosinated microtubules, primary cilia, mitotic spindles, and intercellular bridges, by rapidly recruiting engineered microtubule‐cleaving enzymes onto target microtubules in a reversible manner. Using this approach, we show that acute microtubule disassembly swiftly halts vesicular trafficking and lysosomal dynamics. It also immediately triggers Golgi and ER reorganization and slows the fusion/fission of mitochondria without affecting mitochondrial membrane potential. In addition, cell rigidity is increased after microtubule disruption owing to increased contractile stress fibers. Microtubule disruption furthermore prevents cell division, but does not cause cell death during interphase. Overall, the reported tools facilitate detailed analysis of how microtubules precisely regulate cellular architecture and functions.

Endometrial carcinoma presenting as hematometra mimicking a large pelvic cyst

Large pelvic cysts are commonly seen in gynecologic practice; their heterogeneous origin is reflected in their pleomorphic clinical features. We report the case of a 64-year-old multiparous postmenopausal woman with an unusual manifestation of endometrial adenocarcinoma that presented as hematometra mimicking a large pelvic cyst. In this case, hematometra was well demonstrated by transabdominal sonography, but transvaginal sonography allowed better visualization of the endometrial lining and suggested the correct diagnosis of endometrial cancer. Abnormal vaginal bleeding or hematometra in postmenopausal women should lead to assessment of the endometrial mucosa. Transvaginal sonography can be used to visualize neoplastic lesions in the endometrium when hematometra is detected through transabdominal sonography.