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Rother, F.

Publications and source records attributed to Rother, F..

4 recordsLinked to original sources

Paw posture is a robust indicator for injury, pain, and age.

Inferring biological states from animal behavior is a crucial but challenging step in biomedical discovery that is constrained by variability and labour-intensive assays, even with AI-powered tools. Here, we show that simple images of static paws, analyzed by our custom keypoint segmentation AI-tool provide accurate read-outs for a wide array of physiological states. Without invasive testing, our method detects postural changes associated with nerve injury, acute pain, aging, and the genetic loss of kpna4, a regulator of paw innervation. Leveraging the toe-spread-reflex, a spinal-circuit driven response, the approach requires no habituation and shows low behavioral variability. Individual digits emerge as biomarkers for internal states with digit V indicating neuropathic pain during nerve damage and digit I reflecting loss of kpna4. Our model is freely available and can readily be adapted to other tasks or species. These findings establish unstimulated paw posture as a scaleable, low-cost, readout for biological states.

neuroscience↗

Normal male fertility in a mouse model of KPNA2 deficiency

The nuclear transport of proteins is mediated by karyopherins and has been implicated to be crucial for germ cell and embryonic development. Deletion of distinct members of the karyopherin alpha family has been shown to cause male and female infertility in mice. Using a genetrap approach, we established mice deficient for KPNA2 (KPNA2 KO) and investigated the role of this protein in male germ cell development and fertility. Breeding of male KPNA2 KO mice leads to healthy offsprings in all cases albeit the absence of KPNA2 resulted in a reduction in sperm number by 60%. Analyses of the KPNA2 expression in wild-type mice revealed a strong KPNA2 presence in meiotic germ cells of all stages while a rapid decline is found in round spermatids. The high KPNA2 expression throughout all meiotic stages of sperm development suggests a possible function of KPNA2 during this phase, hence in its absence the spermatogenesis is not completely blocked. In KPNA2 KO mice, a higher portion of sperms presented with morphological abnormalities in the head and neck region, but a severe spermiogenesis defect was not found. Thus, we conclude that the function of KPNA2 in round spermatids is dispensable, as our mice do not show any signs of infertility. Our data provide evidence that KPNA2 is not crucial for male germ cell development and fertility.

developmental biology↗

Karyopherin α2 is a maternal effect gene required for early embryonic development and female fertility in mice

The nuclear transport of proteins plays an important role in mediating the transition from egg to embryo and distinct karyopherins have been implicated in this process. Here, we studied the impact of KPNA2 deficiency on preimplantation embryo development in mice. Loss of KPNA2 results in complete arrest at the 2cell stage and embryos exhibit the inability to activate their embryonic genome as well as a severely disturbed nuclear translocation of Nucleoplasmin 2. Our findings define KPNA2 as a new maternal effect gene.

developmental biology↗

Importin α7 deficiency causes infertility in male mice by disrupting spermatogenesis

Spermatogenesis is driven by an ordered series of events, which rely on trafficking of specific proteins between nucleus and cytoplasm. The importin family of proteins mediates movement of specific cargo proteins when bound to importin {beta}. Importin genes have distinct expression patterns in mouse testis, implying they may have unique roles during mammalian spermatogenesis. Here we use a loss-of-function approach to specifically determine the role of importin 7 in spermatogenesis and male fertility. We show that ablation of importin 7 in male mice leads to infertility and has multiple cumulative effects on both germ cells and Sertoli cells. Importin 7-deficient mice exhibit an impaired Sertoli cell function, including loss of Sertoli cells and a compromised nuclear transport of the androgen receptor. Furthermore, our data demonstrate devastating defects in spermiogenesis that are accompanied by disturbed histone-protamine-exchange, absence of the transcriptional regulator Brwd1 and altered expression of Rfx2 target genes, resulting in incomplete sperm maturation and massive loss of sperms. Our work uncovers the essential role of importin 7 in spermatogenesis and hence in male fertility.

developmental biology↗